For those of you who say your cat "travels" in your fifth wheel, do you mean when you're on the road? I don't know if you have actually ever traveled in the fifth wheel while it's moving, but it's a very rough ride!
Our cat travels in our tow vehicle with us. She starts in her soft sided carrier, then gets let out after half an hour, when she has adjusted. She usually lies down on the back seat for the rest of the trip. When we make camp she goes back in the carrier to be brought in the fifth wheel.
While we're camping she has free run of the camper. She is an indoor cat and doesn't go outside, either at home or while we're camping.