Talking twins, I have to say the 10/1198 with Termis, knocks the piss outta the RC and TL (sorry Jake)

And to go off topic... hit youtube and search "formula 1 v12" and have a listen. Wanna talk about hair standing on end.

Another great sound though, RSV4 with an Austin slip. I heard said bike and exhaust in person...that alone would have sold the bike if I had the $..

YouTube - Aprilia RSV4 with Austin Racing Motogp style exhaust

And RGV250 with an RG500 motor sounds wonderful too

YouTube - Suzuki RGV 500 on rolling road warm up 120bhp