I've been happy with them until their payout for an insurance claim on a rental house's roof of mine was like $1,000 less than the cost of a replacement roof I paid for (through a family connection at a discount). If you're going to come up with a random number, at least send me a contractor who will do the job for YOUR price.... whatever, I'll be looking elsewhere for insurance soon enough.
The two folks I know who had house fires said the experience was the opposite of what you described, with the contractors themselves saying to the owners how much better USAA was to deal with than other insurance companies and much more willing to pay for repairs they (the contractors) recommended with little to no fuss.
I wasn't enthused with my last car repair through them for several reasons but much of it was because of their recommended repair place and not USAA though there were a few things that annoyed me with them but they were minor overall. The price overall is still pretty good for me and I probably couldn't get as good rates or even qualify with the only two other companies I would likely consider right now, Amica and Erie.