Thanks to LED technology, flashlights, as well as bicycling headlights, have come a long way in a relatively short amount of time. I bought a Mag light 4 D cell flashlight back in the late 70's. I haven't bought a flashlight since, but these new LED models look pretty darn sharp.
Nerd time:
These lights look an awful lot like....Light Sabers!!
"Fulfill your destiny!!"
I'm going to the dark side. They get all the babes.
Totaled, that is a very relevant question, regarding whether or not the PB Blaze series is regulated or not, and how many Lumens output they have. My 1W PB still has noticable, usable light, even when the batteries are down to 1v. out, as measured with a Triplett 9025 DVM. As a general rule, I change the batteries when they run down to 1v. I have no complaints about battery life. Certainly better then the Cateye light I was using. That was very dim, when the batteries ran down to this point.