My KK266-R has been happy, though I did do an RMA. First one wouldn't hold time, would lose minutes a day, second one did the same, reinstalled Windows at some point and that went away...so it wasn't the board, just a fluke.
But the RMA process when I did it was easy enough. They were slow on the email, so I called instead and had things ready in five minutes. Cross shipped the boards, no problem.
Their MPX2 looks nice, if I were a fan of dual CPU solutions I may be tempted. Dang...
--Mc