When I got married a few years after high school, I was already in the Air Force. My wife's step-dad was an prior Air Force officer and had my new wife on his USAA auto insurance policy. We got our own policy. Four years later, we divorced and I called USAA to cancel our policy since I was no longer eligible (I was enlisted in the Air Force and USAA was only offered to officers). I USAA representative told me that I was, in fact, eligible since I was already insured by USAA.
I have since added renter's insurance (when I was renting) and now have home owner's insurance through USAA. I have had car loans and mortgages with USAA and currently have several checking and savings accounts, investment accounts, retirement accounts and accounts for my children along with my home and auto insurance policies.
I used to receive phone calls to give me a new quote on auto insurance. When I told them I had USAA, I've often heard, "Oh, we can't beat them. Have a nice day."
Our home was severely damaged during Hurricanes Katrina and Rita... USAA was right there to help.
The way USAA treats their members is outstanding! I have seen cheaper insurance but won't change because I think the service when you need them is VERY important and USAA has NEVER let me down.