I have both a PC 646 and one of the later full-lug models.

My PC 646 was purchased new shortly after they were released. I never experienced the extraction problems that many others have with the PC model. I replaced the stock grips (did not fit my hand and stung a bit after a hundred rounds or so) with Uncle Mike's rubber boot grips.

I don't know if the PC guns were supposed to have an action job; but the action on mine was fairly gritty. Had an action job done by Clark Custom. Vast improvement.

Have used RIMZ polymer moonclips since they were first available for the 646; that made the loading/unloading much more pleasant.

The PC 646 became my favorite (because it was accurate and light) and I kept my eyes open for another reasonably priced one because I liked the one I had so much. Found a NIB full-lug model ( I've still never fired it; though an empty fired cartridge was included in an envelope from the factory) for $500 and grabbed it.