Testing focus on RX10 Mark IV
I used my new RX10M4 at a local kids football game (my daughter is a cheerleader for this team). I put two burst sequences into 4K videos so that you can all see the camera's AF abilities yourselves. I slowed it to 8fps, so you can examine each frame if you'd like.
It's pretty darn good, I must say. I have a Sony A9 and this little beast is not as good as the A9 but almost as good. And, when you factor in the reach (I only have a 70-200 for my A9), the RX10M4 is a real winner.
Hope you find these videos helpful. (Watch it in 4K to see it best.)