Sneaky Microsoft crashing the game (get yer tinfoil hats!)

[Vesuvias]

I wouldn't upgrade to Windows 10 before SE have said their part about compatibility.
Probably not before end of the year either honestly, as there's bound to be plenty of bugs that will make your lives miserable.
Not to mention incompatibilities between third-party driver update handling, and Windows Update driver update handling...

Many of us have been using the review version for quite awhile and have zero problems with XIV itself.