Fastest useable bus speed?

[MikeSi]

Hey, trying to choose a new mobo, most likely either the kk266 or the MSI turbo. The turbo seems to top out at ~145 fsb, while the kk266 cruises to ~155. Assuming a 1/4 pci divider, thats 36.3 and 38.8 pci bus (33 normal?). Can I expect my pci devices to handle these speeds? The thing I'm most worried about is my slave hard drive, which is a Maxtor HD (which I heard is not very speed tolerant) and my network card.

Any thoughts on this? How fast can I go w/o seeing problems?
Thanks