I went away for the weekend and came back to find some cool posts on this thread!
There are definitely benefits in terms of consistency. I still haven't been able to find a vintage zoom with a useful focal length that focuses in the right direction and doesn't have smeary bokeh. Also, I'm not a huge fan of the 12+ element stacked flares that usually come with those lenses. The best I've been able to find it he Olympus 35-70 f3.6 but I wouldn't call it a character lens.
I saw this video about a year ago and tried to get one. I had a seller mislabel their listing and ended up with the variable aperture version. I was pretty irritated by this and it went into a drawer, only coming out when I dropped it off at Goodwill. I haven't looked again since.
Or f4 on S35. Absolutely. That's a case for M43 that is seldom made. But it also kind of forces you into wide, expensive glass. At least for vintage lenses. It's a bit of a catch 22.
Bought this one a couple of years ago. It wasn't for me. I was in agreement that it was the worst Nikon lens I'd ever tried.
I found one of these with an M42 mount a few years ago. I really thought that it would scratch the itch but my copy was remarkably sharp. Amazing for the first zoom ever made.
This is actually a pretty neat idea. It might also work with step-down rings. It could also be a good way to standardize light transmission between lenses. I think I'm going to try this.