Wow, haven't finished the video yet but that AI assisted AF looks very impressive!
For the record, I changed my mind on this and preordered the A7RV and will return the A7RIV.
I think I was grumpy on launch day when I learnt that the initial RRP was $6200 in Australia.
I ended up preordering for $5895 AUD (~$3800 USD) and got a free additional Sony NP-FZ100 battery as a launch promo.
What brought me around to the A7RV over the A7RIVa was the fine details. In order they were:
1. The 8 stops of stabilization is actually legit,
before any lens OSS. This is the biggest one for me. A total game-changer. I hate tripods.
2. Lossless RAW, not present on the A7RIV, and the fact that 26MP M lossless raw is actually a downsampled image from the full 61MP sensor.
3. Sony actually reduced the RRP from what I thought it was. They did a backflip and reduced it from $6199 AUD to $5900.
4. The 9 million dots in the EVF, the same as the A1.
5. Focus bracketing.
6. The new flippy/tilt screen.
Also, after watching more reviews, I am convinced that the AI AF actually works pretty well as it is, and that Sony will be committed to improving it over various firmware updates, as it's improving an existing feature (to be fed into other cameras later on) rather than a new one.