I have a PF9 and love it. I carry it more in the summer than the winter when I carry a larger gun. I have over 300 rounds through it without a hicup. The ejector roll pin is walking toward the hammer. This has been one of the problems some of them had. The newer ones have a new frame that blocks this. I will have to send it back someday for the frame up grade. Would I buy another one? I already have. I bought another one from someone that needed the money more than they needed the gun.
To compare the PF9 to the P3AT I think the recoil is less on the PF9. Some people feel different about that. I think the trigger is better on the PF9. I feel like the problems that they had when they come out have been taken care of and IMO they are a great little carry gun.