I can sympathise with your sentiments in some ways but I'm wondering why you have "a good many russian cameras" if they only take "marginal" pictures? I forget where the quote is from but didn't someone once say the simplest camera exceeded the capability of the best photographer (or something close to that)?
My experience is a little different from yours, perhaps. I've taken hundreds and hundreds of pictures with FSUs and, so far, I've had ONE frame that was spoiled due to "camera error" rather than "operator error".
I bought my first FSU a couple of years ago, on a whim, because I liked the look of it. I loaded a roll of slide film (a pretty severe test of shutter accuracy etc) and gave it a run. When the slides came back I was, frankly, amazed at how good they were. This is from someone who had, previously, laughed at my father's primitive-but-cheap Kiev, although I'd always acknowledged the picture quality. I'd come from a background of "the SLR rules" photography and always thought the Japanese were unbeatable.
If you get only marginal pictures from your FSUs, perhaps you need to look at your approach or perhaps you just need to get them serviced and set up properly.
As for a Bessa, I'm sure it's a fine camera but it's still only a light-tight box with a shutter. The lens takes the picture, with a little help from the photographer. The box just adds convenience and perhaps a few features that aren't, strictly, necessary. I'm wondering how a 70 year-old Bessa will fare...my NKVD is still fit for purpose at that age, albeit with new curtains and a new half-mirror (both still easily available). It's likely to be working when film isn't around and I'm not either.
