AF is generally going to be over-priced, their real niche is doing PPL and IRs for rich guys.
Their CFI program was always a pretty good deal though, and the format was excellent.
The quality of instruction (and management) varies from branch to branch, and tends to be personality driven. You'll definitely want to get to talk to current or recent students. If you talk to current employee, including CFI's who are former students, take it with a grain of salt obviously.