Shab, I 'll chime in with my 35mm Nikkor and 40CV experiences in a minute, but I'm curious, so I gotta ask: how did the switch to/addition of a FM3A come about? For years you've been one of the most remarkable spirit-of-Maitani-ambassadors ;-) (I'm serious though) here on RFF, your pictures in the Zuikoholic-thread are just awesome. You have your own distinct style and a great eye. And the small, unobtrusive OM-bodies and the Zuikos you've been using seem to gel perfectly with that.
At the same time I understand the siren song of a camera with two more stops of shutter speed than OM-1 or OM-2, and the possibilities of the F-mount.
Here's my experience: I used a 35mm f2 Nikkor for many years as my main lens. I *think* it was the AI-S version, and I am pretty sure it had 7 iris blades, not 9. I'd say: it served me well, but it was not remarkable. Bokeh (overall) was not bad, but not great, it had trouble with ghosting during nighttime scenes, and while it was not unusably soft at f2, I never felt it had a truly great balance of sharpness, lens speed and size/weight. Compared to what's possible in the 35mm range with rangefinders, I found it lacking. (I switched to Leica M2 with 40mm Rokkor f2 and later 35mm f2.8 Summaron, and was much happier.)
I also had the CV 40mm Ultron f2 in F-mount for a short while, the very first version. I think it's a really good lens, and it's great to be able to buy a lens that's recently manufactured, and for a mount system that keeps being updated with new lenses (thinking of Voigtländer 28 2.8 or 58 1.4 etc.). But it did not floor me, and I did not gel with the FM2 I used it with. After shooting Leica M for a couple of years it felt clunky and unrefined. I checked out Olympus OM-1 (inspired, in part, by you and your pictures in the Zuikoholic-thread, Sir!
🙂) and liked the experience way more than with the FM2.
(I did even own the now unobtainable 40mm f2 Zuiko for a short while, sold it to a fellow RFF'er who was very happy with it and must have doubled or tripled his 'investment' in the meantime, this was about 10 years ago and prices have been climbing ever since. I really liked the lens and the focal length, it was the closest one could get to the Leica M with 40mm f2-experience in SLR-land, but I was wondering how the lens would hold up over the years if I used it every day (I'm talking about the filter ring being integrated in the moving aperture ring, I would not say it felt flimsy ... just not as confidence inspiring as I would have liked.)
If you're looking for a small walkabout 35mm for Nikon: have you considered one of the versions of the 2.8 35? The six element version maybe:
NIKKOR - The Thousand and One Nights No.38 | NIKKOR - The Thousand and One Nights | Nikon Consumer ? I know it has quite some fans here on RFF, and can be found for less than 200 Euro. But since you are considering the Distagon you're maybe looking for something more modern?
Since you're coming from the 35 f2 Zuiko, which has a certain look wide open:
If you are looking for a lens with a distinct fingerprint (and some imperfections which can be put to use creatively) I'd guess that you'll be happier with the 35 1.4 Nikkor than with other, more 'perfect' options. Are you looking for "soft" or "clinic"? ;-) The 35 1.4 could possibly give you both, as it is very sharp stopped down, but has a bunch of field curvature and sharpness falloff and vignetting wide open.