Sorry if this does not belong here but deals with turbo in a way. I'm going turbo and want 2.5" piping, now my question is what is the difference between the 2.5" exhaust piping from kteller.com compared to buying a exhaust system off ebay that's 2.5", both are SS and ebay has a muffler already. Is there really a big difference don't really care about the product name as long as it performs perfect. Thanks