I'm very impressed with mine so far. The build quality is 2nd to none. I came from a Vamo and while I was happy with it, I questioned its longevity. My 510 connector was slightly tilted and the buttons seemed like they wouldn't last forever. Plus I didn't like how it sometimes took 5 presses to turn on and sometimes 6 or 7. That said, I do prefer the 3 button interface on the Vamo, it's much more intuitive. Don't regret my purchase one bit though!