>>4462595
>rangefinder often needs realignment if knocked out of position
>lenses may not be perfectly coupled to the rangefinder, leading to focus shift that would require the lens to be entirely replaced or serviced (long hunts for a "good copy" of an otherwise perfectly built lens are commonplace among serious rangefinder enthusiasts)
>close focusing any lens with a rangefinder is a pain in the ass and inaccurate
>focusing a lens longer than 90mm with a rangefinder is a pain in the ass and inaccurate
>functionally limited to lenses of focal lengths 28mm to 135mm unless you want to wing it without framelines or, as mentioned, accurate focus
None of the above matter if you use Visoflex, but then you could just get any used SL and have the same (or better) shooting experience with that Summicron and any other native or adaptable lens under the sun, for a better price too.

>>4445820
GR is based, I run a IIIx for daily life and errands and a regular fullframe setup for cooler stuff. In my experience it's not the size of the body that counts (as long as it isn't genuinely enormous like a pro DSLR) but rather the lens, so if you get something like a Z mount camera with small rangefinder lenses (this combination specifically because Z has the thinnest sensor glass besides Leica) it will be very comfortable dimensionally, if you don't mind manual focus

>>4433135
I bought some VM stuff to use on my mirrorless since the lenses are very small and the adapter is way slimmer than any SLR to MILC mount. I'm more interested in balancing sharpness with pleasant rendering and portability over pure IQ at any cost and these lenses hit that mark extremely well. It's a lot of fun, I'm very happy with it.
But as usual, first think about what lenses you want to use and for what purposes, and treat the body only as a means to an end, because that's what it is...