I use the PB 1W and superflash for the rear. I'm sure the 2W is better, but the 1W is still pretty darn bright; certainly enough to be seen. I also have a Romisen flashlight on a Twofish block that I sometimes use. If you poke around on the electronics/lighting SF you'll find that a lot of people swear by the flashlights, at least on a dollars per lumen basis.