I had the Scoobyworld 'afterburner vortex' on my old MY00, lovely sounding/looking pipe imho.

Due to the concerns of the wife about late home arrivals and upsetting the neighbours, I purchased the 'bung' which makes a whole lot of difference and is a good investment for those long 'drone free' journeys.

Vortex £250
http://www.scoobyworld.co.uk/catalog...products_id=76

Bung £25
http://www.scoobyworld.co.uk/catalog...oducts_id=1294