Well, we had the opportunity to use the GPS this past weekend while kayaking the Jackson and James rivers. All in all I'm very happy with the tool. I used the grid coordinates from Google Earth to input into the GPS before taking off and found that those numbers worked much better than expected. I was usually within about 50 to 100 feet of where I wanted to be when the "Arriving at destination" icon flashed.
Cons:
1) short battery life. Got about 18 hours out of the two AA batteries that power the thing.
2) The track map isn't very detailed. It gives a good overall view but isn't going to give much detail when you zoom in.
3)Typing in co-ordinates and names can be time consuming as it's done via a menu up and down instead of with a keypad.
Pros:
1) Very accurate if you can mark your point while standing there. It'll get you back to the very foot you were standing on.
2) Easy to figure out and use with one hand.
3) Water proof. I swam in the river with the thing around my neck on it's lanyard with no problem.
4) Excellent back track feature.
5) Great for beginners as it is simple to use and very inexpensive
If you have any "product reviews" for gear you've used let's hear them.
