Well, let's put it this way. When I use the 3:4 ratio on my Abit BD7-II RAID, it runs neck and neck with Granite Bay and the 850 from the reviews I have read, and you only had to buy one stick of RAM, vs. two sticks for the Granite Bay. So far, the SIS 655 seems a tad slower than the Granite Bay, even when used in async mode.
I would go with a PE based board. They seem to be the best bang for the buck, and you can't beat the stability of an Intel chipset.