Also, this company would appear to produce good (cheaper) alternative to Surefire
http://www.inova-mil.com/products_white.html
From the surefire buyer here, lumen can be measured from the bulb itself or one the whole flashlighth is rigged (with the lence and mirror). Cheap light will se decrease in lumen while good quality light will maintain high lumen output (better mirror quality). Now, how are chinese lumen measured, from the bulb or from the fully build light?