Have had one in my van for the past 4 years, have never used anything from it against anyone but its reassuring that if I am involved in an accident, I can show where the blame lies. I also sometimes like to re-watch the journeys at 16x speed. I also have one on my bike now, its good to be able to keep great video bits of the ride for the future - and I also like it so that I have the ability for a right of reply, if some one does nearly take my life with stupid driving then I have a come back without needing to chase after anyone with the potential of getting into a road rage incident. I agree the cyclist in the video from your OP took it far too far. But how do we deal with the type of ignorant and dangerous driving that initiated the incident? He should of just handed that footage of the dangerous overtake into the police and let the police prosecute. For me the idea of having a camera is, it takes away the need to get involved directly. Are you quite happy with others taking liberties with your life?