Hi:
this would be a very good purchase to make because there's nothing else out there quite like either Cardio K or Circuit Max.
I do Cardio kicks periodically and always enjoy it. It is intense, especially if you give it your all, kicking as hard as you can, punching aggressively, jumping high on the power drills in the second half. I can't see how anyone can do this tape and not get to the top of their heart rate range, especially with those drills, they are awesome. And if you get this on DVD, you could sometimes just separarte the drills section and tag it onto the end of another workout, just to push up the intensity to go out with a blast. After Cardio K, I alway feel this the next day in my arms, and the back especially, in a very good way.
I owned Circuit max for 2 years before doing it, though I previewed it often. I was slightly afraid of it. Then I tried Cardio & Weights at Christmas and realized I love circuit training. Cardio & Weights is significantly easier than Circuit max, and to me they feel like totally different workouts.
Circuit max is like Imax 1 or 2 and Body Max: incredibly tough, a real challenge cardiovascularly, and well suited to a high energy day after a day's rest. having recently challenged myself to do it regularly, I am loving it. I choose to work it slightly diferently in that for the endurance weight work I do not do any upper body exercises at all, I make up my own lower body ones following a suggestion I read from Aquajock, so I use the tape as a cardio challenge and supreme leg endurance workout. This is good because it means I only have to work legs one other day with weight training and I'm set. I find that doing legs only on the weights sections of this tape allows me to accomplish more and i alternate between doing squats, plie squats, walking and static lunges, and lunges onto and off the step. I wish I had not been afraid of this video and had started it years ago!
The advantage of getting Circuit Max on DVD is that if you simply fancy a half hours solid cardio one day, say before doing some weight training, you could run through all the cardio sections back to back and have a blast. I have also done this, even though I have VHS, I just fast forwarded it while jumping on the spot! The cardio features 4 different styles so there's tons of variety. I love the music and Cathe is having fun and very motivational.
I think Cardio Kicks and Circuit MAx would make great additions to your personal fitness library, based on the choice of videos you already own, and there are many ways to work them and include them in rotations.
have fun!
CLare