At qualityflashlights.at ist costs 19.90 €, but you'll get it for 12.95 € if you buy a flashlight with it. So, everybody here would get it cheaper!
I'm not very happy with carrying lamps on my head too. Though I don't care about anybody seeing me, I fear that when I see him or her, he or she wouldn't see anything at all for the next few seconds! Those things are great if you walk alone, if not, the risk of blinding somebody else is quite high.
What's more, you'd need lights that don't whine, as they come very close to your ears, which means no L1D Q5 and no L2D Q5 for me and the L2D is actually my outdoor activities light. Last but not least, we currently have temperatures at about 0 degrees celsius or lower here and it seems difficult to wear the headband correctly together with a bonnet (but not impossible).
Spare batteries on the head? Well, some people wear beercans on their head!
My conclusion : Great idea for the one who walks alone, doesn't wear glasses and wants to have both hands free.