I have a P3B-F, and while it seems to be very stable, it is nothing compared to a Soyo SY-6BA+100.
I had both running in my house at the same place in time a year or so back, and the 6BA+100 was a better board IMHO.
It overclocked my PIII700 FAR higher than the P3B-F and was easily as stable. I loved both but the better overclocker had it's place in my own system over the P3B-F.