I use the Lupine Piko 3. Lupine makes great lights. They no longer have the Piko 3 since they have now updated their product line and have the Piko 4 among others. I have had mine since 2011 and have had zero issues with it, and it still works as it did the day I bought it. I do not use it as a helmet light though, I have it mounted to the bike. Yes, expensive, but it was worth it, seven years old and I still use it, with the original battery, and have no need for anything else. http://www.lupinenorthamerica.com/it...?cID=0&PID=548