Most of the reviewers were extremely satisfied with their purchase of the Insanity 60-day Total Body Conditioning Program. The positive reviewers will agree that it is intense and it is not for beginners but nothing worthwhile comes easy and people are reporting great results, losing weight, losing inches and increased stamina. If you're looking to build muscles P90X might be a better program for you but if you want a very intense cardio workout the Insanity 60-day Total Body Conditioning Program is the right choice.