The Lenser H7 is a good choice. At £40 (ish). A range of up to 150 metres, a focusable beam and also dimable and tilt-able. It is a nice head torch.
I like a head torch as it leaves my Hands free. I also find a torch I am able to tilt (so it doesn't shine in peoples faces, or it shines down as I am walking) good. Being able to dim a torch is great for being able to see instruments and books/ maps and manuals close up. Focussing and beam spread are also good; For me, that is. Different people have different requirements.
I have tried Petzl, Black Diamond, and other makes, some at two or three times the cost of the H7. None have been as good. Petzl do some really good head torches, but they cost an arm and a leg.
The strap fits around helmets. One problem is that the battery containers also is on the strap. Cold can reduce the battery life some what. There are other head torches with longer cables that let you put the battery container in a pocket.
Hval
Edited for repetition, and now spelling.
Last edited by hval; 21st Jan 2011 at 19:41.