I also had one of those law enforcement market P90s; mine came with OEM Meprolight tritium nightsights. It initially had some chambering issues; a quick trip to Ruger took care of that. After that it as a flawless performer; regrettably, I traded it for something else bright and shiney that caught my eye...I had a KP944 .40 S&W for a while gun was excellent, didn't care for the cartridge. I had this PP90DW for 10 years. Probably should have kept it. No malfunctions ever, fired any ammo I tried. Extremely tough.