I have the garmin I que and it is great for caching. It is NOT great for FINDING the cache. You can Import all of the caches in an area to your Ique and then they show up on the map.
You click the cache on the map you want to visit, the Ique guides you there VIA Voice Turn to Turn and then, the Ebook of the cache page pops up when you press the Info Button, it is Great. I am totaly paperless when I cache. I do use my Etex Vista for the find. Once I find the cache I Voice Record it into my Ique what I want to type in the log when I get home and thats it.
I have found a few caches with the Ique and it is a little challanging.
If you have any other questions drop me a email.
Thanks.