I use a Garmin etrex Vista HCX and absolutely love it. I would definitely buy a mapping GPS. The difference between a mapping and non-mapping GPS is whether Topo maps can be loaded to it. A non-mapping GPS will have fewer options and most likely a trail or compass background.

I would also recommend getting a gps with an altimeter; at least its very useful for me in Colorado. I've found my altimeter to be very accurate and its a great help with documenting your scouting activities and where you are and aren't seeing the game. Another big plus is the WAAS receiver which receives the satellite signals and ground station information to give you the most accurate positioning.

My dog just cracked my display screen on my Vista HCX and it was well past its warranty. I called up Garmin and they are sending me a new unit for $89. Thats a pretty good deal considering its a $250 gps.