. . . a A2 LED Aviator. My progression in lights was incandescent AA Mini Mag, 4/7s Quark Mini AA, 4/7s Quark AA/2 and now this. Not dark here yet, but inside a dark room the SF seems as bright on high (120) as the Quark does on Maximum (206). Maybe caused by the SF having a tighter beam with less spread than the Quark. Tint on the SF is MUCH nicer, very natural white looking. The design of the SF clip is a train wreck, the plastic lanyard attachment point looks cheap and the twist from low to high seems excessive. Which SF model do I order a clip from to keep the clip from making contact with the tail cap? Batteries do not rattle in the SF like they did in the Quark, before I wrapped some post-it-notes around them. Been a machinest for 37 years and the SF seems better made, but not by leaps and bounds. Anodizing and electronics I know nothing about. At 4X the cost of the Quark, I think I may have been expecting too much. Going to get to use them in the Sierra Nevada mountains next week and will decide if the SF is a keeper or not.