I have gone almost through the program twice. I just start getting bored with it towards the end of the program. It will do amazing things for your cardio especially the plyometrics. I almost threw up the first day I did it but it gets easier. From time to time, I will take a P90 worksheet with me to the gym and do it for that day's workout. I also have the insanity workout series which is also insane. I just got tired of running and playing bball all the time so I wanted to get my cardio in other ways. If you want the P90x workout sheets (pdf format) for printing, send me your email and I will send them to you.
Also, what sort of equipment to you have? You will need some weights or bands (I prefer weights). You will also need a pull up bar which can be gotten for about $20.