My first bottom fire mech was a Magneto. The button worked fine, but it would work loose once in a while if I didn't tighten the retention ring every day. My second bottom fire was a Nemesis clone. The button on that was complete crunchy crap and eventually failed completely. My third bottom fire mech is a phantom brass Stingray, and that button is heavenly! No issues ever. Short throw, smooth and consistent, never have to lock it unless I put it in my pocket, and it's barely bigger than the battery in it. Try one, it may change your mind about swearing off bottom fire mechs.