This not a Nikkor -- surprise surprise
A few general comments follow below.
The lens is nice once you get the practice of focusing a manual lens, and remember to set aperture the 'right' way. i.e. with the aperture ring. I did a lot of boring comparison shooting today, with the Nonikkor pitted against the Nikkor-N 35mm f/1.4 AIS, Nikkor 35mm f/1.8 S-Line Z, and Nikkor 40mm f/2 SE Z in visible and IR.
In terms of sheer sharpness, all Nikkors mentioned above are at least equal or better at all aperture settings. Wide open, the Nonikkor isn't the sharpest optic to be had, but many subjects or settings still will be fine with its outcome. When these lenses are stopped down to f/4 or more, the differences can be pretty small though. The Nonikkor has a slightly 'warmer' rendition, probably due to the slight yellow tint of the optics, and image contrast is lower as well. Chromatic aberrations were in general low and won't be a problem even for contrasty subjects.
I found the Nonikkor to be a nice performer for IR as it joins the (very) short list of native Z lenses without troublesome IR hotspots.
I'll have the lens with me when I depart for Spain later this month.