Regarding ES vs all the rest, apparently some participants in this thread are longing for a camera that is only silent.
Now as cool as it is to shoot at 20 fps and not put wear and tear on the shutter mechanism, and to be stealthy, the R5 was never marketed as a Global Shutter body. So, while I'd like to see some options for the ES bursts, I still consider the R5 one of the best cameras ever built, and, without any doubt, the best I've ever owned.
(And even if we did have ES burst options, we'd still have the pesky problems of rolling-shutter distortion, right?)
Back to the firmware improvements: Better AF? Thank you, Canon. Incredible already. Reducing the annoying jerking and blackening in low-light, contrasty scenes? Thanks again!
I bought a great camera, and Canon has continued to improve it. I can't say this has happened with too many other products I've bought. (Though I did bring my Odyssey in for some kind of service to the middle seats. Didn't get involved enough to understand what they were doing...)