For what it's worth we have a GPS60 - i use it on my motorbike on my mountain bike, when walking or kayaking or climbing or driving . . . you get the idea!
it's bombproof and simple to use - relatively cheap and it is a nice chunky size so if you have big hands or fingers then it is easy to use!
I always walk with a paper map alongside my gps and a normal compass so it is a backup and caching assistant.
As a walking and caching nabvigation aid it is brilliant!
but as with most gadgets - whatever you will get you will get used to and then like yours best!
whatever you get - enjoy!