USAA in all aspects is the best insurance company, they have never denied any claim I have made, and that was through auto, home, and/or home warranty. They even covered something after the fact (meaning we had the work done and USAA paid us the money back after we got a policy with them).
They were on the ball for my accidents (2), the first they fought some woman who said I backed into her in a parking lot (they won for me), the second I blew a tire and they were there; towing the car, getting me vouchers for medical, giving me a rental, going over every aspect of what they would do for me and the time frame they would accomplish it.
I've known other companies to not offer half of what USAA does and to cancel people for the smallest and stupidest reasons.
Compare them, you'll find that USAA offers far more.
USAA customer 18 years (home and auto), former employee for broad based mortgage insurance company