I'm running at 94.5/450 right now. It seems to work fine. The 100MHz bus didn't work, at 100/400 apps become unstable and crashes whenever they want it seems. It doesn't even boot on 100/450, so I gave up 100. Since the CPU temp is still low (32-36C) I'm thinking of 94.5/500.. That'd an real speedboost from my G4 350. I'll post how it works.
Btw, I don't have an B&W G3, I've got an Yikes G4 350, they use the same motherboard and the same jumperconfigurations.