I fixed and cleaned the fake Model M finally. The key feel is terrible as the key caps are too high. It's become very stiff when the press is not directly going downward.
It's surprising that the board is NKRO but the repeat rate will slow down quite a bit. While I use USB adapter, the board will downgrade to 6KRO but the repeat rate will back to normal.
I may try to de-solder the chip and change to Northgate Omnikey's one next week to see the difference.
So some do have NKRO. Seems that there is some variation then. Binding keys, I've learned, are mainly from the switch tops. You'd want to replace them with ones in good condition to truly restore the feel. Cleaning alone won't do it. Lubing with dry lube gets it closer, but I think once they wear down, that binding won't be totally fixable.
It's like that on my DocuTechs vs my 6085 w/ SKCM Green. The 6085, despite all the switches being clean as a whistle, has binding issues when pressed off center. The DocuTechs, despite having grit in the switches, are very smooth and do not have binding. I cleaned out all of the DocuTechs' switches though, but did not lube them.
I hit up the 6085 with molybdenum disulfide powder, and while it works pretty well, it's not 100% the same. Only switching one of the tops with a less worn top gave it that like-new feeling.
I think this is normal wear or some kind of weird degredation. I'm not sure. The 6085 has no shine on the caps and didn't really have much dirt on the plate either. I really don't know what the issue is.