I suffered some ear damage due to wrestling in high school and have a hard time getting standard ear plugs to stay in place. I found the earlock really held the Surefires in place. I started wearing EP3s in 2008 and switched to EP4s when they hit the market. I always use them "plugged" and supplement them with electronic muffs when indoors or surrounded by walls, especially with rifles. I've never had any problems with them. I keep a set in my shooting vest, hunting pack, range bag and tool boxes. Even though Surefire wants you to replace them after six months, I have used multiple pairs for years. After wearing them awhile, I will put them in an ultrasonic cleaner with warm water and a couple drops of Dawn dish detergent to remove the oil and sweat they soak up.