The price discount listed on USAA's website for buying a new BMW is off US MSRP. I asked my dealer about the program and looking at the details, the discounts is not intended for ED, and you can get a much better ED price from our forum friends.
Regarding finance, idk is they have any limitations on the purchase.
Current: '13 E92 M3 Euro Delivery
Wife's: E36 M3
Gone: E86 M Coupe; E30 M3, E39 M5