I'm mixed on P90X, too. Although I learned how to do straight leg pushups using this series, I also developed bad tendonitis in my shoulder as a result (doing 124 pushups in one workout was exciting, but now I can't do any without pain). My issue with P90X is the repetitive nature - obviously creates overuse injury risk. I just found I started to get bored with it really fast. Some of the discs are way too easy (kickboxing is just silly in this series). So for the price, I don't know that the value is there. The Core video is interesting (I don't like AbRipper at all, but the other one). With that said, I haven't done this workout in months. I'm getting back into Cathe, but it's now slow going because of my shoulder. I'm debating whether to get rid of the P90X at this point. I suppose I'll wait until STS comes out, and decide from there.