I think those that wanted one and chose not to buy (myself included), may buy in the future if and when the price drops to where it should have been (at around $3500-$3800) for what it is
I'm interested, but I bought GFX100RF in April. I'd like to rent sometime the Sony for several days experience, but...
GFX100RF:
-has MF sensor, 4:3 aspect, 100MP
-I prefer a bit the 28mm over 35mm, because of inside shootings, still it has same resolution at 35mm
-the lens optical quality is significant better than the old Sonar
-has tilting screen, I shoot 80% at waist level
-the EVF is different world in Fuji
-better camera body, it's bigger but way more ergonomic, can handheld lower shutter speeds without the IBIS, camera weight centre behind the grip (not front heavy).
-joystick
-smaller lens stick out from body, the overall camera shape is more practical for packing in small sling
-lot better battery life, I just don't have to care battery level or backup battery
-weather protection, lens hood included accessory
-I prefer analogue style shutter speed/iso control over PASM
-better colors (included camera LR profiles, I really like Astia)
RX1RIII:
-most obvious advantage the F2 lens (I prefer sharpness and resolution in only carry around camera if I have to choose because the small lens design)
-Sony AF (not same level as with GM primes because the old motor, and Fuji is capable for my needs)
-compact body (but has more lens stick out, camera is 11mm thicker overall)
-the lower weigh (but harder handheld low shutter speed)
-stiff power switch (Fuji should upgrade the power switch in 100RF, because accidental turn on
Overall I'd definitely enjoy the RX1RIII, but when I have to choose one camera, the GFX100RF. I prefer the overall shooting experience of decent EVF, tilty screen, proper size body over a small point and shoot. In technical aspect I've always considered RX1 as a demonstration of FF compact, with unnecessarily over minimised camera body in expense of usability.
The most important factor in an EDC camera is the lens size, small as possible and the Sony nailed it with the 35 f2 Sonar as the fastest FF compact lens, but downsized the body too much. Fuji is way more practical with X100VI, and GFX100RF, proper camera body with pancake lens.
I purchased the RX1R twelve years ago (when it was first released), then later replaced it with the RX!RII (since sold). I am a big fan of the form factor, lens and leaf-shutter.
My style of shooting has changed a lot, over time, and I now find myself shooting at lower angles with the tilting screen about 40% of the time (particularly when shooting the grand-kids). As such, the fixed screen on the III is a major shortcoming, for me. In this regard, the RX!R III was a huge disappointment!
I suppose that if I am able to purchase a used III in the future for under $4,000 I might do it, but even that remains an uncertainty.
In addition to Sony FF, I also shoot Fuji Medium Format. If the GFX 100RF had a faster lens than F4, I would go for that camera, but it is also too much of a compromise for how I like to shoot.
For those times when I need small/lightweight, it looks like my A7CR with compact lenses will need to suffice a bit longer.
Last days I was making research to find a compact solution with shallow DOF, complementing my GFX100RF, since I prefer the Fuji over RX1RIII, and way too expensive to get beside my GFX. Ricoh GR3x I had is almost same DOF as the 100RF (if I compensate with subject distance a bit), X100VI is also too close. I considered Fuji X-E5 with 33 1.4, but I just remembered there is a camera I was curious past years but have never got at the end. And it is the smallest F2 FF equivalent after RX1RIII: The Canon EOS-M6II with 32 f1.4 lens. I found a barely used pair, and the best thing is it's 1/8 price of a new RX1RIII. Yes, it doesn't has the Sony AI AF, not 60MP, only external EVF, but cheap, has tilting screen, and I can change lens (like the excellent and cheap 22 f2).
