Wheelspinner

I have got a 2001 Classic and looking to replace my current exhaust which is a 3" de-cat Zigen 5. Its way to loud, and I am looking for one which gives me back the Scooby burble and allows me to do track days. The previous owner spent a fortune having the engine rebuilt with a 600 BHP rated HKS crank and a load of other upgrades. The engine is rolling roaded at 350BHP, so I dont want to give up any power. I have heard the Tornado is supposed to be a good system, anyone got any other suggestions?