I went ahead and picked one up for this sale. It should be here today. I'll report on any issues I find.
EDIT: The lapdock just got here.
As advertised, this thing works perfectly well with the Photon. The Photon sits off to the side a bit on the dock in the back, but it's definitely stable, and doesn't look like it will fall out at all.
The Photon's screen in the "mobile view" shows a notification saying "Unsupported Device: This device is not optimized to work with this Lapdock model", but everything seems to be working fine.
The build of the lapdock seems pretty high quality, and the thing is light as hell. I'm pretty impressed, to tell you the truth. The trackpad doesn't seem to do a two-finger scroll or a right-hand-side scroll, so that's a little annoying, but I'll get over it.
The custom build of Linux in the default Webtop seems to be capable enough for what I'm looking for, although I may end up doing some tweaking anyway.
This is meant to be a replacement for my Cr-48 (which is running Ubuntu 12.04), so we'll see after some solid use how this thing performs.