The Garmin eTrex 10 handheld GPS device is the less-featured version of the Garmin eTrex 20, about which we did a full review. The main differences are that the eTrex 10 does not have a color display or expandable memory and costs $100 less retail. The dimensions, weight, and battery life are the same.
See the Handheld GPS Review where we compare the top GPS devices.
The eTrex 20, $200, has a color display and expandable memory. This is one of our favorite GPS for backpacking because it's the lightest GPS we've tested (up to 4.3 oz lighter than others!!) and it has great battery life.