If you'll notice at the actual benchmarks, the Soyo Kt600 has the overal fastest memory transfer rates and comes in second overall in FPS. FPS and transfer rates to me are the most important, as those are the only two benchmarks the human eye can notice. Faster memory transfer rates means better processor performace in multitasked memory intensive applications, like web serving and mail serving. The FPS test is something hardcore gammers look for so they can run there games the smoothest and at the highest bit rate giving them a graphical advantage over there geekie compition.
Tom's Hardware guide in notorious for overlooking the above two benchmarks. I have never been very happy with reviews they have given.
In fact at work I have a Mailserver running the Soyo, a Fileserver running the MSI, and my personal computer is the gigabyte(its the best to overclock with thanks to the dual bios).
For an all around best buy ang for the buck I would go for the Gigabyte board on my home PC, if I had some extra bucks I would go for the Soyo. the MSI is an average board for average bucks. In reality you wouldn't probably notice much of any difference in any of these boards. teh VIA chipset like I mentioned above, is rock solid and fast, and cheap. a good buy.
However the new P4's are faster in all accounts. We have several P4's with 800mhz fsb and man they rock pretty hard but you pay a premium.