Cave Dave, does your arc have fresh battery in it? Mine is only half as bright as an arc with fresh battery. I will be very happy if it's as bright as a arc. Furthermore, I find the LED very blue comparing to my arcs and photon 3. I went back to the store yesterday and compared it to a spaceshot 2 and a supernova on display. Both have similar brightness and hue as mine. Maybe they got bad batch of LED?
I also have a question on the supernova, how many filament does the bulb have? From the product literature it sounds like that it's using different filament to achieve different power level, is that correct?
Finally, I have done a runtime test on my spaceshot 2 with the superbright bulb at high setting. Using 6 Sanyo 1850mah NiMh it ran for 3h 36 min, much better then the quoted 2.5 hour. BTW, while the beam is no surefire quality, it is miles ahead of my petzl Duo. I have several headlamps by petzl and princeton tec and the spaceshot 2 have the best beam hands down.