Spoke with the rep from Head-Direct today about the availability of the 901 in the U.S. Sorry to report that he said it's likely not going to be available here until summertime.
I was able to listen to it for a bit, but without my own music so I won't post listener impressions other than to say it sounded quite good with my JHA 13 Pro FreqPhase. For what it's worth, I was listening through the balanced amp module which he said he expected to retail for $300.
The unit itself is built pretty well but, for the price, I would've preferred to see A LOT less plastic. The top portion, above the screen, is particularly cheap-looking. The physical size of the unit is quite manageable, but thicker than you'd probably hope. About 1/3 to 1/2 of that comes from the battery which can be swapped out with relative ease should you choose to buy an extra. It wasn't quite as easy to eject the battery as I would've hoped, but I can't imagine that a swap would take longer than 20-30 seconds with a few practice runs under your belt.
The interface is decent..relatively intuitive, but slower than I'd hoped. Just expect a slight lag to any button press...hopefully something that can be improved via a firmware update. Fast-forwarding through a song happened too fast. By the time you took your finger off of the button, the song was mostly over. Again, hopefully a firmware update can make this more user-friendly.
Below are a couple of pics I took. Nothing you haven't seen before, but I figured I'm always keen to see additional pics so others might be, as well.