I don't know first hand, but I know someone that took the Falcon in Dallas and said it was absolutely worthless. He said that there were problems with the teacher(s) etc. That's all I know...no real details, sorry.
I don't know firsthand either, though I do feel the need to say that our school warned us off them. They said that for the price, after adding in not only the tuition but also your review books and Qbank, accommodation and living expenses, you end up spending several thousand dollars on it that you could otherwise use to buy yourself a car. We were informed that some students at our school did take these courses -- usually they weren't feeling particularly confident and wanted some guidance -- but for all that they paid so much money, they got scores that were on the low end.
I think you could save a lot of money by just browsing these forums and digging out all the links to Step 1 prep schedules, and digging out all the lists of books that have already been posted, and planning accordingly. In addition, so many hours of lecture per day could potentially take out some productivity, because it leaves you kinda pooped for studying at home, which is often where real learning occurs (depending on your own studying profile).