UPDATE!! Took the PF-9 with me today and shot it. After about 20 to 25 rounds the trigger failed to return. I took the thing home, took it apart, and after much contemplation and looking at the diagram figured out that the trigger return spring is supposed to ride in a groove on the underside of the connector rod. It was not, it had come off of it somehow. Problem solved, but this is quite disconcerting on a pistol that might be called upon to save your life.