Quote:

Epoxy prime before filler is cheap insurance...



No offense but I disagree with this statement.
I think it's expensive insurance!

For example, if you use PPG's DPLF epoxy primer over bare steel,
You spray two coats and wait a day, then apply filler (per p-sheet).
That's expensive stuff plus the delay in time
as opposed going DTM (direct to metal)...

The epoxy primer step adds cost and time to any job...
The real issue here is...is it worth it?

Depends on who your are and what your goal/budget is..

Professional reputations tends to view this as very much worth it!

A Weekender working on his own car, on his own time and dime
(hopefully prepping correctly) may choose otherwise.

Best of luck to you