Damn, if I have the pipe, muffler, and tips already I only have to pay like $100 or even less where I go to get the pipe bended and everything welded together and installed. $600 is way too much in my opinion. One thing to think about as well, those Flowmaster kits are just made out of aluminized steel pipe instead of stainless, the muffler is aluminized steel as well. That's why I don't run a Flowmaster anymore, I had a 40 delta flow and it rusted out way too fast. You can get certain muffler models in stainless though, some of the delta flow ones, hushpower, and I think maybe the new Super 40.