I have the P90X and I love it. I did three rounds of it and got great results! I didn't follow the diet plan, just the exercise. I did two rounds of the classic, one round of the lean. Awesome work out if you can stick to it. I am currently working on my 4th round after having a baby 1 year ago.
Yes, I have the pull up bar and I use it with my program. Do you need it? No, you can modify all of the exercises but the pull up bar for me is something I'm glad I bought. I got it from Beachbody but I've heard there are other pull up bars on the market, just do some searching. Do you need resistance bands? No, as long as you have weights. I have 3, 5, 8, and 10 lb weights. That is plenty for me since I have limited space. I also bought the resistance bands for the program and I use the green band with my pull up bar. Do you need a yoga mat? Yes, absolutely for the yoga and floor exercises, unless you have soft carpeting then you can probably get by without a mat but if you have tile floors, then a mat of some kind will be necessary for your comfort.
Don't let anyone convince you that it's so intense! Yes, it's intense if you have NEVER worked out in your life but if you have any experience with any kind of working out, you will do fine. The key is to modify when necessary. Listen to your body. Drink plenty of fluids after your workout to help with the muscle soreness that will likely follow. If you're sore the next day, push through it but again, listen to your body and modify when necessary. Too many people stop working out because they are sore, they let too many days pass before working out again and discouragement quickly sets in and before you know it, you've abandoned a program that you never really gave it your all. Don't make excuses, just do it. I'm sure you'll become a fan of the P90X.
While the yoga x is an hour and a half of yoga, the other DVD's are about an hour BUT that is an hour of running time. The actually "working out" is around 48 minutes due to the warming up and cooling down, which are essential for every workout but don't be discouraged by comments that the workouts are long. The actual working out parts are not long. Warm up and cool downs are not "intense."