i'm going to get this for my street body, what a great deal. is the light pattern okay since it isn't in the proper ballast?
On a ZX10R, no problem. The Projector type headlamps don't seem to have any issues with the HID bulbs.
If you plan on putting them on a different bike though (or a car) that has the reflector type lamp....be careful. Since the Arc of an HID bulb is not the same shape as the filiment in a conventional bulb, it sends light rays scattering in every direction.
I had an HID on my CBR1100XX. I could light up street signs when the headlight wasn't pointed anywhere near high enough. It looked great for me (lots of light everywhere!), but other drivers didn't appreciate it so much. It blinded everybody. In some states I think they're illegal to install them in a headlight housing that isn't built to accept HIDs.
On a zx10, go for it though. Be careful of the $50 kits on ebay, mine always had trouble getting started. They just flickered for a while.