Tell us about yourself!
I gave up using cheap car chargers shaped like this (in fairness, I had bought a few at the dollar store) when two (2) separate devices of mine - bluetooth headphones, and a bluetooth speaker were destroyed (when one "failed to charge", I plugged in the other to check if the carger was working!). Needless to say, I've been very trepidatious about these circuits every since. My hunch is few usb devices are over-voltage protected, and that these cheap chargers can easily fail to 14v. In any case, I'm not willing to sacrifice any more of my devices to find out!! Best of luck to all.
The funniest part is when you told them, "No, try it - it's really good! As you're eating the dog..." LOL And you just don't stop, even after the event: "On the chance that you have older boys who might like this sort of thing,..." (Yes, my teenage boys love killing puppies, because now they're old enough.) LOLOL Real or made up, thanks for the laugh!