Been there twice for the 4 day defensive handgun class, first time in 2008, the again in 2012. Training is great although I have nothing to compare it to. Both times I was in a class of about 40 people. We had a lead instructor and 2 additional helper instructors. All were extremely helpful and knowledgeable. I particularly liked the professional and patient approach that they took with both male and female noobies.
Not only was the range training great, but the classroom talks about law, personal defense, liability, fight or flee decisions, weapons, etc., were very informative.
I can say nothing negative about the training experience. On the other hand, as previously noted, the marketing of FrontSight by email and sometimes by snail mail can be annoying, but I suppose they need to continue to generate revenue somehow after selling so many lifetime memberships.