OK - I've read the bitter vitriol in here used to describe the use of the
push-in option when wiring electrical outlets, but is there any study
someone can point to that has tested the long term difference between the
screw terminals and the push-in variety? All I hear is anecdotal - kinda
like the resistance a few have for using PEX in plumbing.

Aside from 'personal experience', is there any data?

a