I use the Fenix LD20 and it is probably the best light you can get for $60. It uses 2xAA batteries and they can be either Li-Ion, Ni-Mh or Alkaline; also accepts rechargeable batteries of these types. The fact that you can use three types of common AA batteries is what really sold me on this light. You can purchase quite a few accessories for it as well. I have the older LD20 that outputs 180 lumens max; the newer LD20 outputs 205 which isn't really a noticeable difference. The only complaint I've heard from the new LD20(R4) is that the throw and beam isn't quite as good as the older model. I use a velcro strap to mount my LD20 to my helmet. You may also consider buying a TwoFish Bike Block or Lock Block to mount the LD20 or any other flashlight to your helmet or handlebars. TwoFish Lock Blocks and Bike Blocks can be purchased on Amazon or other online stores. One of my favourite accessories for the LD20 is the white diffuser tip which can be attached to the light to create an aura of visibility around your biking area. It's a pretty cool effect. More info about the Fenix LD20 and it's accessories can be found here: http://www.fenixtactical.com/fenix-ld20.html