I have not done Insanity, but I have done a ton of workouts made by Beachbody: I've done P90X, Hip Hop Abs 1 & 2, Rockin' Body, and I'm currently doing Brazil Butt Lift. I love every one of the workouts I've tried. I'm surprised you were able to download them. I'd be careful about letting that get out too much as the programs are pretty pricey and not intended to be copied/shared.
From my understanding Insanity is VERY CHALLENGING. I considered P90X to be pretty difficult, and I was told by friends that it P90X is a good test to see if you're ready for Insanity. I am still recovering from a bad shoulder injury and a niggling groin pull, so I have put my plans for Insanity on hold for the time being. I have not done it, but I know what you can expect...tons of cardio and plyometrics to the point of exhaustion. Not trying to scare you, but be prepared. This is not an easy program.