It's been a while since the original bad review was posted here. I have something to add.
I bought what was sold to me as a new Numa Nero from an internet supplier, Sonicfiber last month. It turns out it was a B-Stock open box refurb. To make a long, frustrating story short, after a fight, I was able to get them to reimburse me some money which somewhat made it better. I decided to suck it up and keep it.
I can completely concur with what the OP said. This piano is the most incredible piano controller I have ever played as far as feel goes. Yet it all gets thrown out the window due to the flawed midi implementation. You cannot play this piano fast. Everything the OP said is true. My question to Studiologic is if indeed this can be fixed, or is this just the way the Nero is. I am awaiting to hear back from them. I suppose an amateur piano player would not be able to detect this issue, yet a seasoned pro definitely could. The problem is subtle, but absolutely unacceptable.
If they can't fix it, I will be returning it.
Another interesting thing is that they ditched the beautiful, high gloss finish. Numa Neros are all matte black now and they look very cheap. Apparently they were having quality control issues with the high gloss. That could be just BS for an underlaying motivation to cut costs, yet I can't know for sure. It sure is upsetting though, as the gloss Nero really had an elegance to it. In fact, that is part of the way in which it was marketed. Here is a picture of the new matte finish: