A cover is not critical or overkill. I cover mine over the winter. I just use a large tarp, but if I opened my tight wallet I would definitely buy a fitted cover. Friends who use a fitted cover like it a lot, and helps to keep their camper looking good. Big thing with covers, fitted or just a tarp, is to secure ALL the grommet holes with rope or bungee cords. That will prevent the cover from flapping in the wind.
I have no idea if this is important, but I am in Connecticut - our weather is a bit different than Texas. Gotta remember location when asking advice on the internet!
