Garmin GPS Overview
Don't know the other brands. See the links from Redwoods Mtn Biker. Here's the units I've generallly seen used for MTB in the
Garmin line of GPS:
Definition: "waypoints" are a space point that you give a text label and can often display on a screen or map. "Routes" can be made by navigating between waypoints. A "track" is a recording of where you've been, like a bread crumb trail on the screen.
Foretrex: ($140+) Wrist based, no maps on GPS, more for running but used well by bikers for charting ride on PC. It can store up to 10,000 track points (~20 hours of riding).
Forerunner: ($113+) Like Foretrex but more running oriented, no maps. All the Forerunner models can store tracks. [Edit] The new Forerunner models 205 and 305 are effectively wrist mounted versions of the Edge, with the advanced SiRFIII receiver (at the Edge price).
Edge: ($250-$350) More of a road bike odometer replacement. Can't display maps but can store waypoints and tracks of where you went. See my review of it (after reading the online manual)
here. It has the new SiRF receiver and can log tracks for Motion Based analysis.
eTrex: ($150-350) Compact full function GPS for the handlebars, can display Garmin's Topo maps, do navigation, store tracks of multiple rides, altimeter, etc.. The Legend is the lowest cost with minimal memory. VistaCx is the best, with nice color display, barometric altimeter, electronic compass, and removable/expandable min-SD memory.
GPSMAP60: ($350-$500) Bigger than eTrex line, but similar. More memory, bigger display, better reception especially with the new "x" version that has the SiRFIII receiver and removable memory.
The Garmin Forerunner 205 & 305, Edge, and those GPSMAP units with an "x" have the advanced SiRFstarIII receiver. My eTrex Vista without this chip rarely looses signal, but it would be nice to have the SiRF III in thick foliage and deep canyons for those rare occurances. But GPS signals can't go through mountains, no matter how good the receiver.
I really like my compact eTrex Vista, that can be had at a lower price. It's lasted for years through many of my bike frame breaks while on mounted the handlebars. But I may go for the deluxe GPSMAP60 CSx on my next upgrade for it's larger SD chip memory (also on the Vista Cx), better reception, and more software features with bigger display.
Even the Foretrex and Forerunner can do great plots of the ride on your computer after you're back home. See
here an example of all the great stuff the web-based Motion Based programs can do with the tracks from any of these units that store tracks. Click on Dashboard for data, or Map Player and change the background from Street to Topo to Contour to Satellite....
But for MTB you may want to display maps for navigation into remote parts, which would require an eTrex or GPSMAP unit. It would also require about $90 for Garmin's MapSource Topo software that covers the whole US. The street maps also cost another $90 if you want them too. With 24 MB on my eTrex Vista, I can store all street AND topo maps of the entire SF bay area and surrounding MTB parks. Topo maps are much smaller - if you just store Topos, you may store most all of CA with 24 MB.
