I had switch problems too, would just shut off on me and be erratic. Drove me nuts fo 2 days, lol. Would not turn on sometime at all. Lowest strobe setting would randomly come on and a few other things. Cleaned it, tightened the retainer, etc, nothing. Since it was only a couple days old I just exchanged it for my Fenix TK15. I didn't like the way the tail and front spring dug into the batteries either. Left deep grooves and a dent in both my AW18650 and 2 primaries CR123's.With just normal tightening. I got the one bad one out of a thousand probably. I loved tint and beam, it was premium, the best and I loved the light, I'm sure I would have gotten a good one if exchanged for the same light. But the battery marks bothered me, kinda wrecked a new $20 AW18650, maybe the spring was too long or too sharp by mistake. May try my luck again in the future since it was a beautiful light with good reviews.