[dwringer]

For me the most conspicuous thing missing is dynamics... particularly when there are "ghost notes" in between much louder ones during a fast passage, it seems like something is missing.

That said, however, I find it to be oddly satisfying to watch. Curious if experience playing different instruments has anything to do with it. To me, something like a xylophone or a steelpan feels pretty analogous to this.

[fisherjeff]

I think it may be synthesized – I thought the reverb was a little off, and noticed there was little to no change in timbre when the dynamics changed.