great for small spaces
I am doing the p90x and I have a very very small apartment. I also cannot do a pull up to save my life. So I have the complete resistance band kit and I use this so I can do the pull-up exercises without the bar. There really isn't anywhere in my place to put the bar. I like using the bands for these exercises because I can actually do a whole set and I can stay in the workout. If I actually did have a place for the chin-up bar, I would probably do one or two with the help of a chair and that would be the end of that set. With the bands, I am able to get in a full set.
The upgrade kit is pretty easy to hook up. You just stand on the opposite side of where you would be pulling the bands and hook the black safety band to the top of the door hinge and hook the resistance band through.
The kit also comes with a cardio belt which is cool to use with Kenpo and Cardio X. It's like someone is holding you back and you have to fight through it even harder. I use it when I have extra energy, usually with Kenpo X so it's like I'm in a real brawl which makes my punches and kicks more intense. May sound silly, but it really does add a little more intensity.