Our board is custom made, and we have a sbc on com express. This let us develope custom board relativly cheaply, that host SBC with Intel CPU. If you can come up with com express sbc, I'll take it, Amd or Intel. My problem is that all the supported SBC boards, are low in performance.
I'm not sure how do define performance but there is an AMD 785E/sb820 Com Express board http://tinyurl.com/4szzmy5
This should not take too much effort to support. You might have to do some soldering/desoldering with the SPI flash and spend a few hours/days with tweaks. There are also a few 690/600 Com Express boards.
-Bari