Without a doubt, KT266A performance is a notch above AMD 760 boards in most benchies. The Epox board, of all the currently available KT266A boards, is probably the best, but there isn't much competition right now. I had a Shuttle AK31r3 for about 8 hours (until it stopped posting) and I didn't have a chance to run any tests with it. I'm waiting on the RMA from newegg to get the board back. From what I've seen in the comparison tests (and from other people) the Shuttle performs quite well for being about $30 less expensive.
Truth be told, if I was going to wait for a really good board for a single CPU DDR system, it would be the KR7A. I plan on building a dual rig though, and just needed an inexpensive, decent DDR board to stick my extra chip in and the Shuttle definitely fits the bill. I'll be selling the Shuttle/Duron setup once I find a good dual socket A board that I like.
Anyway, end my lengthy rant.
SickBoy