I've been riding with one of these Hit Air jackets for 3 years. I have never had it go off by accident and while I know that an accident may lead to death regardless, I take a small of comfort knowing that this thing will probably significantly reduce my change the chances of bodily injury or blunt force trauma because it is supposed to inflate before I hit the ground. I don't know about T boning somebody but at least if I go off the bike due to a collision I will have some protection. I have watched a number of those stupid collections of motorcycles on youtube being hit by cars and the riders all go flying through the air and skidding for many many yards. How could something like this not help? I only leave it at home on the hottest of days or if it's extremely cold because you cannot put layers on top of it - it may malfunction.