I have been with USAA for years-----have had some issues with the insurance coverage and some 'shady' stuff, but my husband, the wonderfully patient, tenacious bulldog that he is managed to handle those quite easily. They are usually cheaper than other insurance companies and do operate overseas.
Their banking is good - I was with PenFed, but when they stranded me 3 times in different countries and states, I went back with USAA - so far, so good. No complaints here in Germany - I travel a lot and have not had any issues. They also refund all of the damn ATM fees, although I can't seem to get out from under the foreign exchange fee on any of my credit cards.
Investment is OK - I prefer Vanguard.
Regarding unbrella insurance - if you have any infractions or claims on your insurance over the last 3-5 years, they will not issue umbrella insuarance - I tried. Had a speeding ticket (5 over) in CA and they said that made me un-insurable for umbrella - go figure. That's probably how they keep the rates low - I've heard stories of people being no longer insured by USAA due to some issues.
Remember, they are a company in business for themselves. I've watched over the year how they've morphed from insurance into banking and investments. YMMV.
Oh, and if you want to be on their Board, must have at least flag officer status (retired) - 2 stars or better as a minimum......