I don't know who told Lee the Apex has blowback problems but they were smoking rope. That breech plug is a marvel - the only debris I had on the action side of the plug after shooting SWISS 3F behind 497 grain conicals was a couple of flakes of primer residue.
Blowback? Nutz! And I will put the Apex up against the Encore any day of the week so far as quality. The Encore will LOSE. Of course that is my opinion after owning only one Apex but several Encores. There is no doubt in my mind which I would choose again.
The below pic was taken after several shots with Blackhorn and a few with Swiss 3F - nothing had been wiped down.
I would truly suggest restraining from judgmental comments based upon nothing more than unfounded hearsay.