I'll be the first to admit I am not fond of my MT-82, but with a little love it can do it. I think that is one thing the aftermarket will have to accept on their own, a factory transmission with synchros for 8k+ shifts IS asking for a lot.
We shall see. Color me skeptical, but I have been wrong before (a lot, lol).
One question...what street tranny are you going to use to shift - and I mean SHIFT - an engine that spins to 8000 rpm?
A synchronized T56 that can be powershifted at 8000 rpm? I'm sure the tranny can handle the power/torque...but that's a different story.