On a more scientific note, I want you guys to think about this. AVgas is made for aircraft, which run at very high elevations and low RPM.
The only one of those that bothers me is low RPM, which banshee's are definitely NOT. On another note, I have used it and it worked fine, granted I may have not needed the high octane either.
Also, 100LL octane avgas may not be 100 octane either, they measure octane a different way i believe.