(BanditKing @ Aug. 19 2007,16:10) I've been emailing back and forth with Metzeler.
They stated in their email that the M1 +P was specifically designed for the Hayabusa (it's torque and top speed), whereas the M3 has NOT been. As such, they DID NOT recommend using the M3's on the Hayabusa for safety reasons.
Quote: "This bike needs special tires because of the speed and chassis design so M-1 P specs are the only tires approved at this time.
US Metzeler Moto"
Thoughts, feelings?
BTW, I'm using the M3's and absolutely love them over the stock tires. Having said that, I know I don't push the 'Busa to anywhere near it's limit, so I hope I'm okay.