I have the Eissmann sport exhaust with standard centre section (as far as I know0 and its great sound off it. Slight drone at 2.2k RPM but I daily mine and can easily live with it. The other option which is louder again is Hals exhaust off ebay. Its based off the Supersprnt LWR exhaust and has gotten very good feedback on M3cutters. I have been tempted by it. https://forums.m3cutters.co.uk/threa...review.236707/