only thing i can say is that it uses the K2 emitter, which by current standards is pretty inefficient. at this point in time, me personally, i would not buy an led light that is not a new cree, seoul, or rebel, or something more efficient than those three (whenever the more efficient emitters come out).
I would rather buy a Cree light from from Dealextreme. Between 90-120 actual lumens out the front and cheaper too. The Dorcy is probably 60-80 lumens and has a short runtime.