I had one of their kits on a car I sold and I'm getting another one for my new built. I have never had problems with their kits and I had the kit on my car for 3 years before I sold it. For the price, it is well worth the money. I liked it and plan on getting one for my fox body this year and maybe my SN95 for next year.
I do have to say, after building my own kit, I would never buy one. If you can weld well, get some pipe and flanges, and put it together. You could have it all coated when you were done for a professional look