If by 101 you mean Garmin's Geko 101, I bought the 301 version of that one which has the electronic compass and baro altimeter. Mostly it's a basic GPS, but it has the sensor upgrades like Dagny's Foretrex 401. They're all good. Really I got the Geko 301 because it was gray rather than the lime green or yellow of the other two

I tend to use the small, simple GPS receivers more than the larger mapping receivers. All I really want is a hint as to which direction the car is parked. It's rare I get that turned around.