Tom is looking for a GPS replacement for his Garmin and he was thinking about a tablet because it could give him more options. He's concerned it won't connect to satellites for GPS, though. Leo says that almost all tablets he could get have a GPS chip (with the exception of the Wi-Fi only version of iPad), but the maps would get downloaded as he goes. Waze is a great app that does it this way. It collects information about the road ahead from other Waze users. However in rural areas with no 3G, he wouldn't have a map.
He can buy an app that will download maps beforehand. MotionX GPS Drive is the app that Leo prefers. Tom will have to know where he's going in order to cache the maps ahead of time. The Google Nexus 7 for $200 uses Google Maps, which also has a pre-cache option. The downside is that the Nexus 7 is Wi-Fi only.
Julie in the chatroom says that GPS Co-Pilot app is great on the Nexus 7. Also, smartphones like the iPhone or Samsung Galaxy SIII are also solid options for GPS.