Not at all if it is a "good" kit! I have spent nearly that on hand made systems that was not stainless and am completely fine with it. In my GTP I have almost $2k wrapped up in my exhuast, and to me, it is worth every penny, because I know that I got quality in both the build, and the performance! Also, look at APR's exhuast and some others, your saving half on the Blue Flame which is a great deal!

 

It all depends type of piping, size of piping, and if you use a muffler, res, etc. I just say a srt4 turboback and it didnt have a cat, muffler, or res on it. Ofcourse they only came with a cat and 2 small resonators, but thats only on 2.5" piping.