I haven't had this long enough to comment on battery usage or water resistance, but I'm very pleased with it. It is very comfortable and secure, in fact you forget you have it on within minutes. The low power setting is ideal for close up work, and the ability to angle the beam down is especially good when lighting up something you have in your hands, like a book. The full power beam is bright enough for any activity such as walking, running or cycling. I bought this particularly because of its suitability for sailing - the red filter is easily flipped into place and means there is no danger of losing your night sight as you cycle through whites to get to the red - a problem with other headtorches I considered. So overall, it works for me.