In reply to Kalna_kaza:
>Generally only use it for an hour or two at the start of a big day and rarely do planned overnight trips.
How fast do you move?
If walking at night and I want the battery to last all night, I'll have it on the lowest setting. Especially if I'm walking with others and they all have head torches. For running you need to see further, so a brighter setting is good. Cycling you need to see even further ahead.
I have several head torches, but mainly use the Alpkit Quark, which is pretty good for the price. The rechargeable battery, saves money, and I can go out with 100% charge each time, but it can also use standard AAA batteries as well. The zoom, means I can vary the focus from a big pool of light, to something reaching off into the distance for finding stiles etc.
Past a certain point, extra lumens are just a marketing gimmick. Do you really need to see +400m into the distance, all the time? It would be nice to light up a hill side if you were looking for someone, but the cost is a reduced burn time.