I purchased this sight to replace the stock sights on a S&W M&P9 Pro Series CORE. I paired this up with the fiber optic front sights by Dawson Precision as well. The sight is of high quality and the fiber-optics pick up light very well. In low-light or dark, they are not visible, but I did expect this to be the case as they are not tritium. I use the pistol for 3-gun competitions and wanted something to contrast against primarily dark targets and would allow for rapid sight acquisition. These definitely provide that for me. I will shoot my first 3-gun competition with these sights in about 2 weeks. I'll come back and update this review after I put some rounds downrange with these sights.