I had a P9S in 9 mm. Kind of a strange pistol. The roller delay works fine but to decock the pistol the cocking lever is depressed and then the trigger is pulled. I found that to be counterintuitive and a bit worrisome but it does work. There is also a plastic recoil buffer which needs to be present and to spec and it's something of a pain to get at and replace if you can find any buffers. I had three, one in the pistol, two spares. The pistol is very accurate, and popular as a suppressor platform.