USAA typically doesn't ensure aircraft, yachts, motor coaches, and motorcycles.  The first time I was pawned off to another well-know company as a USAA "preferred" customer, I ended up with a $3500. annual RV insurance premium.  I quickly figured it out, cancelled the policy, and landed a great policy with another company for $1650.  Recently, I was pawned off again for a new motorcycle. Flo quoted me $385./yr.  I looked elsewhere and immediately found more coverage for $255./yr (30% less!!!).  So my friends, the days of trusting USAA to take care of us are long gone.  Think carefully before you get in a canoe with "Flo".   


Regarding the above comment,.  In the case of aircraft insurance, USAA does have  a partner company.  They offer USAA members an additional discount  in addition to a AOPA discount.  Can't comment on the other coverages.