Due to the recent addition of a non res cat back Milltek exhaust, I am contemplating selling the standard quad tipped twin exit system, rather than hang on to it, to return the car back to standard when I come to sell. Is this a wise move do people prefer the car as original as possible when buying? As the original is quite a size, due to it being one peice. Nothing wrong with it at all, only covered 40k miles. Thoughts??