Likewise, I have a 60csx with a Dell Axim PDA and now I have the Nuvi 500. Accuracy while in walking mode on the Nuvi was within 4 ft of my first test cache find. Logs and hints are quickly available. There is even a comments feature that doesn't seem to be quite friendly for later viewing. Additionally, Wherigo is also playable. The unit keeps tracks so you can re-trace a big day of caches.
You have to copy the GPX files into the proper directory (GPX) on the Nuvi to be able to access the prior logs and hints. Oh BTW - all caches show up on your screen with the proper icon type for that cache. If you use mapsource to push the caches into the Nuvi like the 60csx, they turn into waypoints and the logs aren't available, neither are the hints. To make it worse, if you do both of the above, the caches will have 2 icons per cache, one from the mapsource and the other from the GPX. As it stands now, I still will use the PDA since I already have it, but the Nuvi is very nice for having the info all on one device, and it tells you how to get there! Still trying to get a full understanding of all the Nuvi features. So far = Very Nice.
BikeNfind - Jerry