My two cents, based on what I do for after effects.
If you are rendering for intermediate use, set gamma correction to none.
It will look right in After effects, it is right, BUT it is wrong in Quicktime, with or without the FinalCut Compatibility check box.
If you want to make Pro Res for viewing purposes only, set gamma correction to automatic. Quicktime will now display it properly, however the file itself will be wrong.
If only you could manually set gamma tags in all quicktime files.
If only Quicktime would stop trying to “help” and just display the file exactly as is.
In a year or so it will hopefully have died the death it deserves anyway.
Unless someone else can come up with a movie container that lets you set all the metadata properly.