How about Westwind in Phoenix, AZ?
Modern Fleet (load of new Archers direct from Piper this month, all Air Con, GPS, etc..). 100% Instructor Retention on the Airline Prep Program, very busy ATC environment (I've been, it's busy). Heard from an ex-instructor who did the course and spoke highly of the place.
An I only seeing the good bits here? I've heard Sierra is better, but if low $$$ is important surely this is the one? A guaranteed instructor position has to be the best you can get.