insanity workout

anyone tried this workout?  i am contemplating purchasing.  any input much appreciated.

I've never even heard of it. What does it entail?

Heard about it but havn't seen it.  Fitness buddy has been on it who breezed through P90x and said Insanity was good.

thanks fried

Almost tried it but after reading through many reviews on the website and others I decided against it as the concensus says it's very hard on your knees. 

I've got a few P90X vids and more Insanity vids (not a full set of either) and one thing I noticed is that P90X is good if you're just starting out and have never weight trained with dumbbells before.  Insanity is more cardio intensive and WILL kick your ass.  IMO, I get a better cardio workout from Insanity than running, but it still doesn't quite get you in "game shape" if you ever were active in sports throughout your life.  P90X has a better abs routine but for me, nothing has beat the free 10 minute pilates abs routines free on Comcast's On Demand. 

Thank me later.