I’ve used PF and GAP as my go-to barrel-turners/profilers dating back to 2007 for GAP, and maybe 2014 for PF.
Got my last 2 Criterion pipes from PF, both Grendels.
My Obermeyer and Bartlein pipe’d AR-10s built by GAP have been lasers, as have the PF pipes.
There was a PF Bartlein Grendel was the most accurate AR-15 I’ve ever shot. Mark sent me one to independently test for a customer who was complaining it wouldn't shoot. I took photos of the 8rd groups and told Mark to tell the customer if he didn’t want it, I would pay all his costs for it plus some.
It was a 20” Grendel that shot 8rd bugholes with ease. He quickly said to send it back once he saw the photos. It was just a case of not knowing how to shoot gas guns. I think he was free-recoiling it without strict fundamentals. I wanted that upper pretty bad.