I was issued my CS-1 in 1988. Already M stamped. As a Customs supervisor I carried it from 1988-1993 when we went to 9mm semi-automatics. Mine was not turned in, rather re-assigned to a Customs special agent who carried it for several more years. I ultimately located it in 2000 and bought it. I can assure you that revolver has had many thousands of rounds through it of both 38+P and 357 mag. Performance was flawless. Nuff said!