I'd have to agree with the PS series, they would definitely complement the CTX series nicely, however, I'm not a Firmie so I cant make a comment there.
Did you know that if you order 4 videos you get the 5th one free, plus a $15 discount, plus free shipping????
Butif you only really only want 3 I can list just 3 for you but what are you looking cardio or more strenth?
Dawn W