I think its pretty good. It fits AW 14500's and the Efest 14500 flat tops just fine. No gaps and center pin adjusts to take up the battery slop for no rattle. Also like to add it doesnt feel like light cheap junk in your hand. It has a nice solid feeling.
I lubed up the bottom switch on mine. It wasnt exactly rough but not perfectly smooth if the switch was pushed on a angle. Its still not perfect but ok and getting better. ( A little light sanding of some edges prob. would have eliminated it) All
threads were perfectly smooth after a lube. I cant complain...................
I dont know how to measure voltage drop but if its there its not noticable to me.
I run a penolope and its clone on it. They fit nice and look really good together.