The best motorcycle I've ever owned has been this 2000 ZX-9r. Here she is as she looked after I picked her up. She was a basket case then, crashed, unaccustomed to high altitudes, pinged, hesitated, and just ran poorly (2008).
And as she looks today, replaced stock muffler, rejetted for high altitude, crisp throttle response, and runs amazing (2009/2010).