I used one on the Air Chair i build for Aim. Them things are a sonofabitch to put on. You gotta drill like 50 million holes but they are secure, i would just do a weld on myself. It will take 20 min of welding and you can even box the frame to make it look nice.
They arent bad kits for people who dont know shit but have $$$. I just engineered and prototyped one for a 98 toyota tacoma at work. It had everything, triangulated 4 link, the works.
i love the wheels that we decided to put on there. I was gonna ask Joe how much $$$ for them but i know he wouldnt give em up