Traded my 18' 350 for a 22' CFTP 500. Pulled these off before letting her go. I have used the race pipes w/res for 6k miles. They are louder than with cats but sounds wonderful! They are in perfect condition and with the additional spacing (before the spacers it did throw a CEL) for the post cat O2 there has been no CEL for high emission levels or anything else... you could smell it at times though. Installation is simple... hardest part is the top nut on the stock cats (access from the top) This was the best power adder I was able to do. Look in my other posts and you'll find pre/post dyno of these and it was impressive. $800 pipes