Brynnb,
Back when I was still actively teaching at a cessna pilot center, I can remember that those students that had used the Cessna Multimedia training system made significantly faster progress on average than those that had not. I noticed that students using the system grasped new concepts much easier and would learn new manouvers in the aircraft much quicker than they would otherwise. I would say that the extra money spent on the CD's will be recouped many times over by saving many hours of expensive dual instruction in the aircraft.