From fidian
Positive:
1) Has terriffic autorouting and it can say the directions to you if you have the car kit.
2) Water resistant (does not float).
3) Relatively inexpensive - you can get one for about $100 on eBay.
Negative:
1) Has no compass "go to" mode, so you are stuck finding the cache by using an overhead map.
2) You must take out the batteries to have access to the memory card, which is how you would add in waypoints.
3) Built-in antenna is great for outside, pretty good for inside the car, but can be foiled by foilage.