Without a data card installed, the eMap has a built-in map of the United States (highways and major routes) and low-resolution map of the world (border outlines and major cities). This feature alone is superior to most GPS units that were out only 2-3 years ago.

But it's with the data card installed that the eMap shines. You can buy either pre-programmed cartridges from Garmin (an expensive proposition) or install blank 8- or 16-megabyte cartridges and upload your own map data into them. Garmin's MetroGuide USA CD-ROM gives streetlevel maps of the entire USA; their Roads & Recreation gives topographic detail maps of the US; and their WorldMap gives medium-resolution maps of the rest of the world. Unfortunately, you'll need either a Windows PC or a PC-emulator such as SoftWindows in order to install these maps, as Garmin hasn't allowed any third-party developers (such as GPSy) to license their map upload protocols. Follow this link for some tips on how to upload maps using your Macintosh and SoftWindows/Virtual PC.

The eMap is considerably thinner than previous designs. It runs on 2AA batteries for about 14 hours. Unfortunately, the thinner, lighter case is also less waterproof. Unlike the previous designs, which could handle a drop into water (provided you yanked it out quickly enough), the eMap is only splashproof and water could easily ingress into the main compartment.

The eMap uses a different data connector than the other handhelds; which means that low-cost third-party data cables aren't available for it. If you want to hook it up to your Mac, get the eMap Deluxe kit, which comes with a PC-data cable; then either use the Keyspan USB PDA Adaptor to hook it to your USB-Macintosh, or our generic GPS adaptor if you have an older Mac with serial ports.

People who loved all of the data screens that previous Garmin units provided will be a bit disappointed. The eMap is designed for consumers who will use it to walk around cities or day hiking. It's been considerably "dumbed down." The eMap has only one main map screen and it's difficult to get all of the data you want (lat/long, speed, bearing, altitude, etc.) on one screen. Of course, for 99% of the populace, all they want is a little blinking icon showing them where they are on a map, they wouldn't know what to do with a latitude even if it were provided. But this means the 1% of us that do know and do care are disappointed.

The eMap Deluxe is an eMap with an 8 megabyte data cartridge and PC data cable. Since you'll need both of these if you want to have any detailed maps or interact with it in any way, it's highly recommended that you make the plunge, spend the extra $40 and buy the eMap deluxe now.

Pros: Lightweight, great battery life, good screen.

Cons: New, flimsy data connector. Not waterproof. "Dumbed down" for consumers.

The eTrex line is Garmin's latest series of smaller, ruggedized handeld units. There are a variety of eTrexs (Summit, Venture, Legend, Vista, etc.). Most of them run for aroud 20 hours on 2 AAs. They are definitely recommended if you're hiking in the backcountry and need multiple display formats in a very hardened case.. It more or less replaces the GPS 12 series from Garmin. Unfortunately, it doesn't have all of the data screens or display formats of the older units. But it is built very solidly which is more than we can say about the eMap, which isn't even waterproof.

The basic eTrex has no built-in maps, memory, or data cartridge support. It's good for hiking, but really you should shell out for the money for one of the higher end units. You'll be happier in the long run.

The eTrex Summit is an eTrex with a built-in digital compass and altimeter/barometer. The altimeter/barometer isn't aviation grade, but it's still very useful for hiking/climbing purposes. It also helps stabilize altitude for the GPS calculations, like some of the older Magellans used to. The eTrex Summit unfortunately doesn't have any expanded map memory support.

For expanded map memory (which acts like an internal data-card to upload topo or street maps), you need the eTrex Legend, Venture, or Vista. The eTrex Vista is the top-of-the-line unit with 24mb of uploadable map support, America's Highway database built-in, compass, barometer/altimeter, and the kitchen sink. Unfortunately the Vista only has a 12 hr battery life (the sink uses up a lot of energy). For more info on these products, see Garmin's eTrex page.

Note: GPSy X does not currently support the USB-based Garmin units, including the various models that end in "Cx" or "CSx."

Note: The eMap and eTrex series require GPSy 3.37 or GPSy Pro 1.17 or above.

If you have money to burn, the StreetPilot is ideal for use while driving. The screen is large and vivid. The maps are accurate and detailed. The interface is well-thought out. This unit easily rivals some of the dedicated $1000+ car navigation systems; although its main missing feature is the ability to find the best route for you automatically. You have to manually "string" your routes yourself (or use GPSy); since the SP series doesn't have enough CPU horsepower to do this for you. But once you do do this, you'll get nice "TURN LEFT AT I-95" guidances towards your destination.

On the negative side, the StreetPilot has less "geek" features than the other units in Garmin's line. It only supports latitude/longitude (DDMM.MMM) display in WGS-84, so if you want UTM/MGRS or other display formats using other datums, well tough. This is a pain since USGS topo maps are usually best read in UTM coordinates and use the NAD-27 datum. If you're not a hiker or if the above two sentences were gobbledeegook for you, then this obviously isn't an issue. Other negatives are that unit is quite expensive after you factor in an external antenna for best performance as well as a MetroCartridge or two. The unit is much too large for use while hiking and there doesn't seem to be an easy way to handle-bar it onto a bike/motorcycle either.

The StreetPilot ColorMap adds a full color LCD display (slightly smaller than the grey-scale) for about $150 more. People who have used both have said to go for the ColorMap, unless your unit lives in a very sunlit area where the color LCD washes out a bit more than the greyscale one. Of course, $150 buys a lot of low-fat yogurt, so the decision is yours.

That all said, the StreetPilot series is easily the favorite unit for non-hiking and non-motorcycling use at our office. The screen is just to die for and the map details are fantastic. Now that you can upload maps off CD-ROM, it's a killer unit. Just help us convince Garmin that they should release the map uploading protocol documentation out to trustworthy Mac developers (like ourselves).

For information on how to upload maps using the Garmin MapSource CD-ROM on your Mac, see our Garmin VirtualPC FAQ.

Although this isn't a GPS unit per se, this active GPS antenna is highly recommended for use with any handheld GPS units, especially the single-channels. It's a must-have for vehicle use if you have limited satellite visibility. Its footprint is approximately 1.25" square and has an embedded magnet. It is waterproof and can be mounted outside your automobile/boat. Some backpackers even use the Lowe mounted to their frame pack because of the Lowe's superior sensitivity in low satellite visibility conditions such as deep forests or canyons.

The antenna comes in either a BNC connector (we replaced the stock straight BNC with a L-shaped one in this photo) or a MCX for use with the Garmin 12/12XL series. Please note that the Lowe antenna is a 5V powered antenna and is not compatible with the 3V output of the eMap. Check with your GPS vendor and with Lowe to make sure your antenna is voltage compatible.

That being said, for under $150 this is a pretty solid unit. It's well sealed against the elements, and extremely tiny with great battery life, so it's a good candidate if you're going hiking with a topo map (just don't lose the topo map). Reception from the 12-channel parallel receiver seems excellent and it uses a higher-quality quadrifilar antenna than most low-end units which use patch antennas. Unfortunately, the orientation of the non-adjustable quadrifilar antenna in the GPS 315 isn't ideal, it should be pointing straight up for optimum reception, not at the 15-30 degree angle that you'll normally have it when hiking.

If you're aware of the limiations of this unit, it's a fine choice. Personally, I think you would be happier spending the extra $50 and getting a mapping GPS unit such as the two mentioned above. Built-in maps do make a big difference, despite what old-timers will say about the hazards of depending too much on your GPS unit and not enough on your compass and topo map (which you should always have if hiking in the backwoods regardless of your high tech paraphernalia).

The major downside of this unit is the expense of the data cable (an extra $40 for a PC-type DB-9 cable). Also, less third party software supports the Magellan data transfer protocol.

Magellan also sells the very inexpensive Magellan GPS 300 for less than $100 street. This is not recommended as it has absolutely no computer communications capability so you will be stuck entering waypoints by hand and have no ability to back them up or edit them. Spend the extra bucks to make yourself happier over the long-run.

The Garmin GPS III+ has an improved basemap of the entire U.S. including all major highways and many major routes, with exit information. The maps allow much better navigation since you can actually see the roads on the display and you can use the names of town/cities in your GOTOs and routes; as well as knowing if there is food/gas/lodging at the next exit.

The GPS III+ also adds the ability to upload about 1.5 megabytes of maps to it. Unfortunately, the map data only comes on a PC CD-ROM and Garmin has not announced any plans for a Mac version. Furthermore, even though Global Mapping Systems has offered to license the protocol and pay a royalty, Garmin is also not allowing any third party vendors access to their map uploading systems. The good news is that if you have a relatively fast PowerPC (G3) recommended, you can upload maps using VirtualPC or other emulator. The uploadable maps are high quality street level and make this unit indispensably fantastic.

Please note that the screen of this unit is rather small (this is a handheld unit after all), so unless you have very good eyesight, it isn't really suitable for use in an automobile. We'd recommend the StreetPilot or ColorMap below instead. On the other hand, this unit works great on a motorcycle or snowmobile.

Garmin has released an international map CD-ROM, which our non-U.S. friends might want to take a look at. It's cheaper to go with a U.S. version GPS III+ and international map CD-ROM than it is to be an international version GPS III. Go figure.

For information on how to upload maps using the Garmin MapSource CD-ROM on your Mac, see our Garmin VirtualPC FAQ.

The GM100 is a good unit. But it shares some design flaws with the Explorer units it supersedes, such as a dinky battery compartment; inability to use an external antenna; easily scratched screen; and bulky feel. There is less support for the Eagle/Lowrance units in terms of software and in this reviewer's subjective opinion, the user interface is more difficult to use. If you're deciding between a 12XL and GM100, go with the GM100 for the maps. But between the Garmin GPS III/III+ and the GM100, the Garmin beats it with a better overall quality of finish in both hardware, firmware, and software.

The Magellan Map410 is an updated version of the GM100. It has better mapping capabilities but is still lacking compared to newer units such as the Garmin eMap which has removable, reprogrammable data cartridges. On the positive side, it is considerably more waterproof than the eMap, which can barely handle a light rain.

The basemap of the U.S>. release GPS III includes highways and major routes in the U.S. and outlines of countries and major cities, internationally. There are international models with slightly more detailed international maps at a much inflated price. You may be disappointed with the resolution of the international maps, so look before you buy. You may have better luck purchasing a GPS III+ (U.S.) version and uploading international maps off the CD-ROM using a friend's PC or VirtualPC.

On the other hand, if you can find one of these on fire sale, go for it.

There are some minor differences in the user interface:

• The II+ lacks the audible "beeper" of the 12XL and also lacks "proximity waypoints" that help you navigate shoals, mine fields, and other hazards
• The II+ is extremely easy to mount on a dashboard and has a standard BNC connector for easily attaching an external antenna.

If you were purchasing a GPS for purely driving/boating/biking and other vehicular activities, we would recommend a Garmin GPS III+ or StreetPilot because of its case design. For mixed vehicle/hiking or for pure hiking, the eMap or 12/12XL's design works best since there is no antenna to catch on your pack and the flatter form factor fits easier in jacket pockets.

• Excellent price performance and rugged body
• Excellent battery life, good backlighting, and clear screen
• Powerful 12-channel parallel receiver allows it to lock on even in difficult situations (such as inside a vehicle or in a city/forest environment)
• The GMRN/GMRN waypoint transfer protocol is widely known and many software programs support it
• On top of that, it has strong NMEA-0183 compatibility

Both the Garmin 12 and 12XL are ideal for hikers since are small, have very long battery lives and no external antennas to catch or break on something. The lack of built-in maps isn't as much of an issue if you're already working with a topo map and compass (which you should always have; since GPS units are known to run out of batteries or fall off ravines at the worst possible moments).

The main "cons" of the GPS 12 are that as a handheld unit, it doesn't mount very easily on a dashboard and that it lacks an external antenna connector. It also doesn't have any built-in maps. However, we don't think you can find a better GPS in this price range.

The bigger-sister GPS 12XL has an external antenna connector and an audible "beeper" to help warn of approaching waypoints and dangerous "proximity" waypoints (handy for avoiding shoals and reefs for marine use). Unfortunately, the GPS 12XL's external antenna connector is a difficult-to-find MCX type rather than a standard BNC. Whether or not an antenna connector and beeper are worth $100+ is your decision -- you should also look at the GPS II+ (below) if you are considering units in this price range. If you have money to burn and want to use the GPS unit in a car or RV, purchase the Garmin StreetPilot (below).

The 12CX adds a color screen.

We would still recommend a Garmin GPS 12 over the Eagle Explorer since the Garmins have better computer support.

The cons of the Eagle Explorer are an unusual data cable plug that is not commonly available and exhorbitantly priced; difficult on-screen waypoint management; no option for an external antenna; easily scratched screen; truly outrageously expensive accessories ($120 for a rechargeable battery pack!); and internal battery terminals that are apt to break or disconnect easily.

GPSy is the only Macintosh program that currently supports the proprietary Eagle/Lowrance data transfer protocol. To connect an Eagle Explorer to your Macintosh, please see our cables page.

The Eagle Expedition is the big brother to the Explorer and adds more waypoints, better battery life, and some other snazzier features.

We were disappointed with the display quality of the ColorTrak. The "color" display is more akin to the color LCDs used in cheap handheld games, and not a real color display such as in a laptop. Of course, given the power/size constraints this is understandable -- but the eyestrain wasn't. Because of this, we recommend the Tracker over the ColorTrak. We recommend that you physically touch and handle one of these units before purchasing to make sure it meets your needs.

Magellan has told us that the ColorTrak and Tracker use the same data protocol as previous units, so GPSy should work just fine with both of them.

The DeLorme Tripmate used to be a good solution even up to several months ago. It provided a fairly decent 12-channel parallel GPS engine at a low-price (~$180 bundled with StreetAtlas). But oh how the times change! Now it's possible to buy a Garmin eTrex for about $140 which provides equal or better receiver performance with the advantage of a screen display and full pocketability.

So now the Tripmate, which requires an attached computer or laptop to run, and which doesn't store any waypoints or route markers itself, seems a bit outdated for the times. There do seem to be some niches for it, for example it would work well mounted permanently on top of a RV or boat that always has the laptop going at the same time. But for everyone else who occasionally gets off and hikes, or who wants to program their GPS with waypoints, there are better solutions.

We haven't yet evaluated the DeLorme Earthmate, which replaces the Tripmate. By all indications, the price performance of the Earthmate will be much better. Whether this offsets the lack of a screen and programmable waypoints remains to be seen. GPSy has not yet been certified Earthmate compatible, but we remain committed to making it 100% compatible within the next release.

We should state for the record that DeLorme has hired Karen Nakamura as an external software consultant and that she wrote the GPS engine for Street Atlas 4/Macintosh and that we have licensed Tripmate/Street Atlas ® support for GPSy from them; but we do not otherwise have any financial stake in their success.

"I (Karen Nakamura) used to have a GPS II mounted on my motorcycle (1979 Honda CX500 Custom) handlebars and it worked very well on my long tours. I used a Lowe antenna when using the GPS II in my car (1993 Honda Civic) since my low dashboard blocks most of the sky and I got much better performance from the active antenna unit. The unit works fine with its stock antenna on my motorcycle. I've recently switched to using a Garmin GPS III+ in both vehicles."

Current Magellan 3000XL/4000XLs have 12 parallel channels, but the older ones on some dealer shelves have only 2-channels. Magellan apparently didn't want dealers to have to return the old boxes and so the only visible differentiation on the boxes between the old and new models is the new part number ("00-62014-010"). Make sure your dealer will allow you to return/swap your unit if it turns out to be an older 2-channel model. The Magellan 2000XLs are dual channel units, I can't imagine any good reason to buy such an outdated receiver these days, return the product and get a Garmin GPS 12 instead.

This unit has been seen sold "as-is" for less than $100. At that price (including an antenna), it's a wonderful toy to play with -- as long as you have a "real" GPS to back you up.