I've only used MobileHelp once when I had trouble breathing. I was in the bedroom and my base station and mobile unit were in my office. I pushed the button on my pendant and couldn't hear the mobile unit or the base station. MobileHelp called me on the phone which I was able to answer and tell them what the problem was. I have a lock box on my door, so the fire department was able to come in my house and help me without breaking down the door. One other time, I accidentally pushed the button on my pendant and didn't know it. I was on a road trip in a very isolated part of Wyoming. I got back in the car and heard the voice on my mobile unit and was able to let them know nothing was wrong. I was happy to inadvertently find out I could summon help in a highly underpopulated area, as well as in a city. It's money well spent for great peace of mind!