To me it's all vaporware. After the 1DXMKIII being such a disappointment for us "low life" still sports shooters.... I don't think Canon is anywhere near a professional body that will show a marked improvement in IQ with an OVF. Canon pushing the MKIII for the Olympics is almost laughable. It's a very modest "still" improvement and to be considered and upgrade is insulting.
The IQ is horrible, the color rendition is flat and muddled, definition lacks, noise in shadows at moderate and low ISO show clear green and purple, DR is very poor in contrasting areas, the ovf focus points when using single-point are hard to see, the awb is off to such an extent on some settings that we felt there must be an upgrade or firmware fix or something coming, the reader the camera came with does not work, wi-fi and communications protocols are not intuitive, the scrolling menus are nice but static, shooting mode should have large easy to read and responsive indicators in the VF well lit. Canon got the 1DXMKIII so wrong and it's buggy with some lenses, strobes and flashes, Now we want to talk a bout "another" pro body??? How about they get the one that came out a few days ago right first??????
Frustrating seeing promos, marketing and rumors to boots interest or sales in a future camera(s) when others are left baffled at what Canon is doing "Today" in "Reality" where we expected a "flagship" that was supposed to be a marked upgrade for still sports photographers. How do you not improve IQ???????