I've just fitted some made by 'G & G Bike' that I found on www.redracingparts.com
The thing I liked was the option to fit an insert which mutes the otherwise straight through can. Unfortunatley, I got mixed up on the order (doh!!) and am still awaiting the inserts.
The cans themselves, in titanium, are light and very well made. The titanium welding is just brilliant. Only thing is that without the inserts the cans are astonishingly loud and have set off the odd car alarm (Great!!!). I'm looking forward to the arrival of the inserts to achieve the middle ground between standard and anti-social.
Prices not too bad either and I'm sure the sticker can be changed for something a little more 'fashionable'.