Got the JCW muffler installed onto my 2013 R58 S. The JCW muffler has only been on the car for 1 day, so I believe it will break in more and gain some volume. Here is a video comparison I put together:

 

Were you expecting the JCW exhaust to be very loud?

This is pretty much what you will get without the factory JCW engine and the complete exhaust line but just the muffler.

It sounds good to me.

 

I wasn't expecting it to be much louder, that's why I went with JCW option vs aftermarket. I wanted a nicer deeper tone without getting a lot of drone and the JCW was the best choice.

Really enjoying it right now, but as with any exhaust, they get deeper and gain slightly more volume as miles are put on and muffler is broken in fully. I will drive with the current setup for another 1k miles and I might do the resonator delete.