I guess it depends on the target market too, studio cams needs are more about IQ than portability, and if you wanted to be mobile doing street photography with MF, perhaps the smaller mirrorless makes sense, and cheaper to build, but would force an immediate lens line up issue so that offsets any ease of build in my mind... and I'd still want a decent evf to look through personally, which puts some of the bulk back into the size. I have no interest in going back to rangefinders, heh. There will probably never be a pocketable MF, or FF for that matter, so might as well just stick with something like a KP with small grip and a LTD prime, or just go with the GRIII,
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