I have used USAA since early 1999, and been nothing but pleased. I have filed something like $35K in claims during this time (only about $2K of which was my fault - an at-fault accident in 2003 - with the rest paid out for a stolen car, a vandalized car, and a parked car badly damaged by an uninsured driver). They have been a pleasure in every respect. I use USAA for my banking, mortgage, homeowner's insurance, and many of my investments as well.
I don't think it's fair to call USAA's membership policy "thinly veiled racism" in that it allows service members to join, regardless of their race and sex. Since the US military has, for example, a greater percentage of African-Americans than the population as a whole, USAA is disproportionately available to African-Americans.