Aaron Morgan and I own this bike and I use it for track events with Ti2TT in on the West coast.
We bought it from a salvage yard with a bent frame.
Sent her off and had the frame repaired and I have to say after Jeremy Toye did a little dyno work with it and build us a custom map for the Power Commander this bike is a ton of fun at the track.
Compared to the Kawasaki ZX6R with Ohlins this bike wins in the handling department hands down. It is so stable and smooth everywhere.
Power wise it does not have the low end grunt the 636 had. You have to ring this motor a bit. However after a trip to Lee's and Jeremy Toyes tuning the bike has a much better powerband. if I had to choose between the ZX6R or the Gixxer I would pick the Suzuki.
The Suzuki is just a better bike and more refined than the 636 was.

