Finally got my hands on one of these a few days ago. Waiting for Dante to be realized, so I'm giving it a spin with the unsupported fw400 using a $10 fw400 to fw800 adapter. With fw400 and a 64 sample buffer size I can run Presonus's "Capture" to record all 52 inputs simultaneously and the Windows DAW CPU meter never crests 3%. Can't try out 88.2 or 96 kHz due to my 25 foot long FW cable.
I did have a UC Surface crash though while running it on my DAW, so the jury is still out, I'm hoping it was an isolated event. Need to keep pounding away on it while the return window is still open. I want this to work!
Compared to my rack full of 4 m-Audio Octane's this thing really runs cool! Love the lack of a fan, its dead silent.
Anyway, it seems to work OK, haven't tried it with SONAR yet, but will soon. The potential for eliminating wiring and excessive heat producing gear in my studio is staggering. I hope it works out!