I have a 08' 550i w/ the Mpkg that I'm replacing the rear diffuser on to accommodate dual/quad set-up. I found a nice set of tips that are VERY Unique. I just want to know how much of the sound of the exhaust is designated by the tips? or is it all in the resignators, mufflers, etc I'd hate to spend the money I'm going to spend on these tips knowing that it is all aesthetics and in turn ultimately not getting the benefit of the same money spent on a "brand name"

TIA

 

Tips have no effect on the tone of the exhaust at all, but since your car currently does not have a quad exhaust you will have to reconfigure your exhaust system to accommodate the quad tips. The reconfiguration will end up changing the tone of your exhaust.