Haven’t used one on an open gun but have one on a 40 cal duty weapon. It has held up great to daily carry and full power 40 rounds in slide mount. The dot is very bright in comparison to all the others I’ve compared it to. (RTS2, DPP, RMR, both vortex’s) There is a GM in Midwest using one his open guns. Last I heard he was over 10k on it and happy with it. Sent from my iPhone using Tapatalk