One more vote for Scorpions:)
i may be able to get a carbon can from the states for same money as an alu here, so when i have the cash in a couple of months that might be the way to go me thinks
trouble is i have textile winter gear at the mo but no summer stuff, might have to sweat my way through first years riding 
the problem with that shexy street extreme scorp can is i think you have to do some serious cutting
I too am looking for an after market can for my cbr600f 04!
Improving the sound is one thing but I was wondering if you can get any more power from an aftermarket?!??!
get a stubby with a removable baffle they sound good
went for a Fuel exhaust a couple of years ago;)
sound good with baffles out, MUCH smaller than stock and very good prices