The Sig P320 M18 is enjoying immense popularity thanks to its adoption by the US Military. Whether it should have one or not remains a hotly debated topic, but the gun is here to stay either way. The modular Fire Control Unit allows for new grip modules, slides, and all other manners of customization while keeping the same serial number. The bore axis is a little high, and the trigger isn't the best, but it isn't the worst either. Overall, most of the issues someone may or may not have with the M18 can be rectified by its huge aftermarket. It is a solid duty pistol that is proving to be popular even in the civilian market.