Ya, I've done it. Did crossfit for about 6 months, got good strength gains, but not much change in my body. Did P90 for about 70 days, lost 17 lbs and 7% body fat. I'd recommend it to anyone who has the will power to stick with it. Just started it again this week, you are gonna be miserably soar for the first 1-2 weeks, but it will grow on ya.
