I used them and got great results but PLEASE remember that you cannot spot train! As in, you can't just decide, "I'm going to lose weight around my hips and butt!" and then magically that's where you'll burn fat. So yes, these videos will help you tighten those areas, but there is no guarantee that you'll lose fat from those areas specifically.
That all being said, the workouts were fun, effective, and easy to follow. The instructor is cute, and he sounds like Borat, heh. I was very happy with the workouts overall. Good luck!