Mine acted funky on the second day that I had it. It wouldn't stop strobing. I couldn't switch it on/off, it just kept strobing. I took the battery out and left it for a few days before getting around to requesting an RMA. Put another battery in it, and it was fine.
I have no idea what that was about, and I'm hoping it doesn't happen again. I've used the light every day as my primary work light with no further issues.