'Turd in a punch bowl' haven't heard that one in a while. Yes, it is true that some owners have experienced a 'rattle' when installing an 'off-road' X pipe. But it's not the X pipe that is rattling. If you look at your undercarriage, there is a hugh shield on your mustang. The sound level increases quite a bit when eliminating the cats. This sound level is sometime enough to make this shield vibrate a little. You need to isolate the vibration and then insulate it with some type of spacer. This issue is for the off-road X only, not the X-pipe being talked about in this thread. I stronly suspect almost all off-road X pipes could create this vibration, this is not just a Pypes issue.

 

This price was an introductory special. They are normally like $120