I have this video series and think it is pretty fun. It is definitely different but it is a break from the usual and I think it does a pretty good job of working you out. It will not give make you lose incredible weight but will definitely be worth it to try something new. I have also bought a couple other of the YBB videos at Target and love them too.
I really love these videos, I am usually a runner/biker and have been craving something fun and new. The workouts are a fun combination of dancing/aerobics, ballet exercises (for your BOOTY and believe me they hurt) and yoga. After the workouts I always feel great. I think they are a good supplemental workout if you are into doing "doubles" - a good run or walk in the morning and the YBB videos at night. Even on their own they are a fun workout and def. made me sweat.
I think they're fun for a change of pace. They're kind of campy/cheesy, but enjoyable and I definately sweat while doing them. I do them once or twice a week to change up my routine.
I have all of the DVDs and do them on a regular basis. They seem to be shrinking things that ought to shrink and they are fun. A little goofy at times, but I don't really mind all of the new agey stuff.