I went with MS, in Olive Branch. TO register, any address in MS was ok, no hassles, or documents required to substantiate address either. Renew annually in person or by mail, all you need is credit card or check, no questions asked, no inspections.

As a long time USAA member I found having my airport car on a separate policy w Geico to be a better deal than keeping w/ usaa. I was very forthright with both geico & usaa reps about the airport car, my family cars at home, where it was to be kept and the infrequency of use. Both provided quotes, on multiple options.