Just picked up a pair of these because I've been wanting to upgrade to electronic ear pro. Found them for $6 at this weird dollar store near me that gets old Wal-Mart stock and resell it for pennies on the dollar. Anyway, came to find out that they were missing a volume knob and microphone cover on the right side and had someone's initials on them with paint marker. Threw some new batteries in them and they at least work, but haven't taken them to the range yet. Emailed customer service at 3m, told them my predicament, and got an email back in an hour saying that a replacement knob and foam cover would be sent free of charge. I'm very impressed with the outcome. Should be going to the range this weekend to see for myself, but does anyone have any experience with these, good or bad?