I also believe I-Max is easier choreographically but more intense in terms of cardiovascular challenge AND leg challenge than either I-max 2 or I-Max 3. I did I-Max 3 as produced for the first time on Friday, and although I was dog-tired from the workweek I was able to get through the entire workout without really feeling like I was being pushed to failure, even during the many-million-plie-jack interval.
What's nice, though, about I-Max 2 AND I-Max 3 is that each of these is more finely chaptered, has the Mix-N-Match feature, and each of these has blast-only or blast+recovery premixes that get you more quickly to each blast with a quick touch of the button. I plan on working the I-max 3 blast-only premix into my ongoing rotation, and have been increasingly using the Mix-N-Match feature on I-Max 2 to just do all 10 blasts in a string with no recovery.
I-Max 1, however, remains my favorite, and the standard by which I judge all interval workouts. It was the first Cathe workout I ever did, and almost everything has felt easier since.
A-Jock