Hi Sapphiregal. I used P90X two years ago. I lost some weight, got in a little better shape, then got tired of seeing the same workouts, same faces, same unfunny jokes. I was able to keep up with most of it including phase three. I haven't put in any of the CDs since August 2010. The yoga cd is too long (over an hour) so I would skip some of the beginning and the end and just do the harder middle part (around 50 minutes). I pulled a leg muscle three weeks into the program doing the jump squats. I also discovered (after I bought it) that I hate working out in my living room (or any other room in my house).
After seeing the infomercial, I think that Insanity would be even worse for getting little injuries from jumping around. I would probably buy the program if I was younger (20's or 30's).
Right now I am running and biking and lifting in the gym two or three times a week. I weigh 10 lbs less than I did after P90X (mostly because I'm not bored), and am in better shape.
Sorry I can't be more positive about these, but I'm just one person with a neutral experience. If you go online (other than the Insanity and P90X websites) you might find some other independent reviews.
There is an independent review website that I use at www.chasefreedom.com. P90X was on there. Insanity was not.
I did P90X too during my off season. I was hoping it would help me put on some muscle but I didn't notice much of a difference. I agree the workouts were just too long for me even though I'm used to hours of running or biking. I didn't complete the program because I ended up getting injured - not from the videos, but the videos did make the injury worse. I haven't done the workouts since, but my husband still uses them. He doesn't follow the program but every other day he does his own cardio workout and every other day he'll do one of the weight training videos from P90X. I have a few friends who have gone through the whole program once but haven't heard of anyone who liked it enough to go throug it again. Seems like most people will pick a few workouts they like and use them to break up their normal workout routine. Don't know anything about Insanity. Hope this helps.