I have both sets and love them. I've just finished the 30 day Xtrain cardio-strength rotation and started Zcut in an attempt to lean out more. I usually do 2 of the cardio back to back on one day (+ or - the bonus abs); 2 strength one day; and mix in a couple other metabolic workouts for variety for that week. I add one leg strength day with Cathe as that is my problem area. I have to say, I am surpisingly sore, in a good way, as Zuzana has a few creative moves and sequences that really provide a total body workout. For the price of $15 for 3 DVD's, it's a great bargain.
I joined Zgym to try it out for a month and actually just joined for a second month. The Zshred that she does I think takes it up a notch. It's amazing how much you can sweat in such a short amount of time. I'm so amazed as what it has done for me and I thought I was in pretty good shape to start with. I have leaned out so much in my core. Try it for a month, you can always cancel it at the end.
I did strictly BodyRock work outs for about 6 months when Zuzana was still a part of it and I was very happy with my results. I did not feel the need to supplement with any other work outs. I would not have done it for so long if I wasn't happy. You can also go online to her new website and get free workouts of hers to compliment the Z-cuts if you want. There are probably some longer ones there. She used to do some longer work outs when she with Body Rock - up to an hour - though her claim to fame is definitely being effective and EFFICIENT thus the shorter work out times. Another thought is to double up work outs if you want a longer one....do 2 back to back!
I have both and the power yoga. Love them all. When I do strictly Zcuts more people ask me what im doing because it looks like I'm leaning out. The workouts are creative and you sweat like never before.