Favorite or best?
Tracy Anderson Metamorphosis Omni - I used a rebounder for the dance cardio portion, most used single workout, I'm still amazed I didn't tire of that over three months. Lost weight, ate better, and the thing that I really liked was my core strength & balance were best during this 3 months. I think instead of talking about it I should go back to it for those reasons alone. I like her, she's no nonsense about what works for you, and that it will work.
P90X - original classic program I did 8-10 weeks combined with running. It was tough to combine the two. I thought the program was very good & balanced, although if I did it again with running I would opt for every other day or just 2-3 days per week P90X, alternating with running.
Interestingly, if I hadn't done so many Cathe rotations I might not have been able to do either of those rotations, I'm positive all my Cathe rotations built up my cardio endurance & strength from absolute beginner to an almost advanced level. Nothing to sneeze at, at age 50.
My favorite rotations, looking back are the ones balanced with cardio & weights, equally through the week. Okay, maybe a little more cardio.