I wouldn't expect any major difference in performance of 2 mainboards using the same APU and AMD Chipset anyway.
But it's good to have some details on the "small" things like SuperIO Chips, sensors and so on.
Good to hear that Multi GPU works in fglrx since with APUs it really makes sense to have it once you decide to put a dedicated card in.
Still all of them are gaming desktop related and currently I'm looking for smaller office / HTPC like things.
Stop TCPA, stupid software patents and corrupt politicians!