Originally Posted by E90Company
Yes, but he has to remember changing the downpipe to anything aftermarket, catted or not, will void the warranty. You are messing with emissions equipment, and the dealership could bring up backpressure/O2 issues/etc if you modify it. So I would say BMW PE with stock DP (Safe route with warranty, less performance, more sound), or C-Less downpipe stock exhaust (Quieter, more performance, warranty void).
Good points, thanks. What do you have on your car? I may just get the PE for now and enjoy it. I am less worried about the warranty as I am the potential smell from going cat-less. Which is why I was wondering about better catted DP's, but that does not sound like it is worth the money. The BMS DP just seems like too good of a deal for the price if I can put up with the smell.