GPS questions

I was told by someone the reason Moses got lost in the desert for 40 years was he was a man and men don't ask for directions! With that aside have any of you used or are using GPS guidance such as Garmin Street Pilot or the like?
If so how do you like your unit? Is it easy to use? What types do TM owners use (survey) I can see some advantages to using one, however at a cost!
Any help is appreciated

Midwest Dave