Hi,
I ordered one of these, and have been playing around for a few days.
I am demoing this as a midi keyboard. Haven't tried the internal sounds (except for the piano sound, sounds much worse than say Ivory II, Garritan or Pianoteq.)
I had previously tried the earlier model Studiologic 88 Grand, which has TP-40 wood, whereas the Numa has TP-400 wood. Didn't really like it. A bit hard feeling, at bit on and off. And what bugged me the most - the sensors are not very well placed. If you do not strike down the key from the top, you cannot get a high midi value, no matter how much you accelerate the key. Affects repetition as well.
Anyway, I have tried VPC-1, MP11se and casio 510, so comparing to those.
I prefer the feel of the VPC-1 (but it is too heavy for me, most importantly it has too much upwards pressure even after you press the key)
My comparison at home is a baby grand 186 cm.
So:
As a keyboard it is, I think, really good. A bit like the earlier 88 grand, but much more control throughout the down movement. Easy to play pp. It also has simulated escapement, which the 88 does not. It is also a tad lighter I think, but might be remembering wrongly.
I actually like it more than MP11se or Casio 510, but that might be mostly me. MP11se to me felt a bit mushy, and a bit too light for me, though I know many like it. MP11se has proper pivot length, which makes a difference in feel, still I find it somehow easier to control the sound on the Numa GT. The Casio also had a bit more toy-like feel. This is a bit surprising, since the Numa is a folded action, whereas the other two have long pivots. Maybe it is mostly a preference of weight - the Numa as a bit more initial resistance than the other two. To me it kind of emulates the sense of connecting the the hammer before you accelerate, so to speak.
You feel the lack of pivot length. It comes across as a difference between black and white keys, and difference in playing at the top. Especially at the black keys playing at the top is noticably harder. The black keys are a bit heavier as well.
The escapement sensation is nice, but the sensors are placed in the same wrong way, which makes it a bit weird: is push the key down silently to just when escapement starts, and then accelerate though it, you get no sound. On a real grand you get a sound of course, since the escapement tells you you are still in contact with the hammer.
Still it bothers me less then on the 88 Grand. On that one the sound always felt a disconnected (I blamed the sensor placement, maybe it was just the feel of the keyboard). On the Numa it feels very nice and natural.
On the negative: still it has a bit of that hard, on and off feeling of the 88 grand. hard/stiff sensation when you it the keybed, and and a bit on-off "switch"-like feel. I guess that is lack of pivot length. Still easy to control though, but a bit unrealistic in that regards. Compared to the VPC-feels a lot less realistic.
Very nice texture on the white keys.
Easy to play fast and hit notes without being light. Tried the Pianomarvel SASR test for fun, got 1648 which is pretty good

Probably won't keep it. Since I am using it only as a midi controller paying for all the other stuff is a bit unnecessary, kind of hoping Studiologic will release it as only controller (like the 88 grand).
Thats it, if you have any questions let me know, probably keep it a few days, then return it.