Originally Posted by Shmelgy
A friend of mine had the stock muffler paired with the gintani catless xpipe for a day, and that sounded like shit between shifts (DCT) but not bad when it was being floored. My setup doesn't have any rasp. If you go the bypass method, you are basically straight-piping it and if you delete your primaries it will be LOUD. If you don't mind loud, then go ahead and do it. I think by leaving the secondary cats in was a good idea since there isn't that much of a smell compared to fully catless- if you care about that shit.
Do it and post some videos!
If I went catless, the OEM exhaust modded muffler would have to go for sure. It's already pretty loud as it is, and the rest of my setup is completely stock. And I've also heard M3's with straight pipes (on Youtube) and not a big fan at all. Too loud and too raspy.
The only other good setup that I've heard was full catless with Borla exhaust. But I think I'm going to go with what you did. Thanks!