We just starte insanity this past week, so I can't say which I like best. We are following the schedule, which seems to start and repeats 3 videos and then transitions to others. We are p90x and The Firm users, so we were excited to try something new. I definitely sweat more than anything, but its doable! Get it used on amazon and save yourself some bucks.
Re: NBR - Insanity