My Dad is retired USMC, so I had USAA auto insurance through him. This was my insurance company until just a couple years ago (slightly over 20 years).
USAA has excellent customer service. Unfortunately, I was able to test the expediency of their claim processing three times over the years that I can recall. 1. My car was broken into when I lived in Miami. 2. An elderly man plowed into my car on 95 in Virginia when I was on the side of the road changing drivers. 3. And right here in NC, a young college student plowed into the side of my car as I was driving down the road minding my own business. And I have to say, each time USAA was super quick and wonderful to work with.
Once in my late 20's I shopped around to try and find a cheaper insurance. About the 3rd place I went to with my policy in hand to try and find a better deal, I was actually told by the insurance agent to stick with USAA because as long as I was single and did not own my own house, no body else could beat their price!
Well, then I got married and bought a house. Here's where the con comes in for USAA (and the reason I rated them at a 4 and not 5). It pains me to say this, but I jumped ship. USAA just does not offer the wonderful deals that other agencies offer for multiple cars on the policy and house insurance.