I am the new owner of a QZI 18650 (brushed and brass) mod and i must say it is very nice. The button takes a little bit of love to get right. If you do not have it set up correctly it will move a little side to side. My Patriot RDA on top and an 18650 battery inside does make it heavy enough to fire on its own if standing on it's end with the switch unlocked unless you set it down as carefully as possible (i've fine tuned it to have a short throw) but the reverse locking ring is easy enough to use so not a big deal. All in all i do love this mod. It hits like a Mack Truck and looks great, what more can you ask for!