Expired Provia 100F (120 format, 2012/2013) - worth it?

[MattKing]

I suspect E-6 may hold up better than C-41.

It is the narrow tolerance for colour shifts when projecting that makes out of date slide film problematic - slide projectors don't usually include colour editing functions.
If you are scanning (or for that matter printing with Cibachrome, when that was possible), you get an extra chance to make some corrections capable of reducing the effect of most problems.