When I worked for the guh-ment we tried out compensators on our M4s. They made our rifles easier to control when firing sustained full auto, but the flash was unacceptably bright. We were taught to just shoot pairs when on full-auto, anyway; something that is easy to keep on target without a comp. Soooo...we just stuck with the standard flash hiders. Now on our Barrett rifles, we left the muzzle brakes on...