IIRC they are led by tracey mallet and mostly pilates type moves. anything you can get on tracey's dvds and relatively cheaper too(especially if you catch the workouts at ross). i like her as an instructor but i just don't see her breaking away from the pilates stuff she is famous for so i doubt these will have anything different on them.
Ya know, I haven't heard of this workout, but I really like doing crunches. I find them very satisfying to do, especially if I put my hand on the part being crunched and feel it contract.