I JUST installed it. Didn't do anything with the settings.
Just tried 5kFF and it doesn't like it until its 1/16th res. Big difference, but you have to realize it's another 3rd bigger at something like 13.8mp vs 4k which is like 9mp (I think).
Argument to shoot 4k unless you specifically need that extra resolution maybe...
EDIT: I think the 2.3 has more L3 cache or something as well.



