Navy Federal Credit Union
First off, banks figure out ways to nickel and dime you for their bottom line. In general, Credit Unions do not. Specific to Navy Federal...I signed up with them when I was in the Navy. They have always been incredibly competitive on rates with other CU's, and they flat out kill the rates at banks. We learned this as my wife worked at a bank and her 'employee rates' were worse than NFCU.
As for the negative reviews...something doesn't quite add up. I've never personally talked with a service member or vet who could not get a manners hip there. I have referred dozens of them that direction and each has had no issues at all.