It was on my first day’s testing with the R5 that I got a DIF and it clinched it for me that the R5 was a keeper. It locked on so quickly without any discernible lag. You just need patience and wait until they slow down.
I can't resist posting another Migrant Hawker DIF, shot 191, on my R5, the first day out with it for testing, following shot number 188 posted 19 Sept. I literally shouted with glee when I chimped this as it was the best DIF I had ever got. This was using the 100-400mm II + 1.4xTC. There are some snarky comments on FM about the 1.4x on the 100-400, but I have found it excellent, and on the R5 it focusses really fast. This one is closely cropped to show the detail you can capture. These shots sold the R5 to me as I could have returned it. You have to see this at large size to see the detail.
To be honest I am a little surprise this "slow" speed works so well.
If I try DIf I normally choose 1/1600 or better 1/2000. And I have the EOS R which is not the perfect camera for this challenge. Espacially if you want to catch a pair laying eggs in the water.