I having been using this light for several weeks and am happy with it. I am a daily bike commuter (over 40mi daily)and usually both directions are in the dark. This is light is part of an armament of lights I use, and I think it is effective high above the road on the back of my helmet. My only issue is that I carry a small backpack which partially obscures the light when I am in an aggressive posture. Sitting up higher or dropping the bag lower helps.Overall, very good product so far and no complaints. I look forward to seeing how it handles the rain and colder weather.