My circuit board arrived today, and on initial inspection looks good. I got lucky and received 3 copies of the board. There are one or two minor blemishes in the flood-fill ground copper, but all of them are in large areas and not in places where there were tracks or anything critical, so those won't matter.
Fits nicely in the box, the keys mount properly (not so tight that you have to force them, but firm enough that it takes a bit of pressure and the posts will lock them in place and prevent rotation), the Teensy fits (plugged in from underneath), and the connectors fit well.
Next thing is to actually get the components soldered onto the board - and find out whether I screwed up the circuit...We did try really hard to check it before sending it off to be made though, so I'm hoping it all just works. :-)