Forcefed was gracious enough to have me over to play show and tell with the Plum Crazy lower he has so I was able to see one first hand. Mating it to an upper seemed to be a bit tough with the tight tolerances on the lower, but once installed it seemed really solid. The trigger was surprising for a factory lPK. It was a bit stiff, but there was hardly any creep, broke very cleanly, and there was no grittiness that could be associated with the LPK from somewhere like DPMS. The fit and finish looked good. No extra flashing like you see on cheap molded plastic, it seems that they took their time to either get the manufacturing process right, or clean it up really well at the factory. All moving parts were solid and smooth. All in all nothing really felt "plasticy" about it like I was expecting.
Still on the fence about buying one, but this has certainly given me food for thought.