I agree with all about Plyo X. The one reason I like this workout is that it INSTRUCT you on proper form on Plyometrics. Many end up hurting themselves, and yes Cathe is a blast, but she is not doing this for 60 minutes either. This workout is intense and I noticed firmness in my whole lower body through this workout in the P90X rotation. Also, Core Synergies is an EXCELLENT workout. It concentrates on your whole core, including the back. I could not even do all the moves initially, but when I was done with the rotation, I could. And that is saying something. These two workouts I would not trade for anything.