The Plek machine does not automatically produce perfect fret work. It will not correct production issues such as sloppy filing of the fret ends. I think much of the complaints seen about Gibson’s fret work are mostly about cosmetic issues rather than playability. I also think that after the guitar leaves the controlled environment of the factory and is exposed to temperature and humidity changes during shipping and warehousing, the neck could require adjustment by the time the customer receives the guitar, which is of course not Gibson’s fault. I will add that the nut on my 2010 Explorer was definitely cut too low from the factory, to the point where the B string fretted out on the first fret when played open. Not a big deal to fix though. I have personally not had any Gibson with playability issues (other than the Explorer’s nut) , but I also know how to completely and perfectly set up my guitars. But from an aesthetic point of view I’ve seen some pretty poor workmanship on necks with very visible file marks on the fretboard and very sloppy filing of the binding around the frets.