At the last NHL game i shot, I was speaking with a Sony shooter for the wire service and we both agree, you can NOT shoot an entire game at 20 frames per second and actually manage to edit each period and caption and file 6 to 9 images during each intermission. It cant be done. High speed mechanical shutter on the R5 is more than enough. The only time I went 'full speed" was during a shoot out during regular season and I did not even look at all the players who did not score. I jumped straight to the game winning goal and dumped the rest. It is just too much for the vast majority of needs.Yeah flash sync at any speed would be a big deal for some, but if the R3 can do 1/250 or maybe 1/500 that would probably be enough for most people. But will those same people want only 20MP or so if they are not sports journalists?
I could see using it for certain moments at Tennis, but again, never the entire match.
40 frames per second is niche territory for sure!