I use Ultra-dot red-dot on my big boomer handgun. 500 Mag, 480 Ruger, 475 Linebaugh and S&W 460 Mags. With over thousands of rounds, they are hold up well. In my opinion they are one f the best other there for the price. Now if you want to spend more money, look at the EoTech, I have one on a custom 510 GNR Encore barrel.