To each his own.. i have a friend that runs an exhaust shop.. and if it didn't throw a CEL i'd have done it yesterday to get rid of the stink
You would need a tune to keep your vehicles mpg from dropping. If the smell is worth that kind of money, or getting less mpg than cool. I would suggest having the exhaust shop fit a tail pipe that turns to the side similar to the 3rd gen, I think others have had this done and it supposedly helps.