I've have a light and motion Vis 180 micro tail light that I purchased from my LBS a few months back. I really like the pulsing action as opposed to the flashing of my other lights and went for this unit specifically due to it's USB charging.

I recently went to hook it up to the charger which requires opening a small rubber door to access the port, doing it without my reading glasses and instead pried off the rubber cover which seals the switch, a real dunce move. Turns out in order to reinstall it you need to open the unit and do it from the inside and there is no obvious way to open it like it's glued together.

I decided to contact L&M to see if they had a suggestion on a fix sending an email after hours. I got a reply early the next morning wanting to know my mailing info and a bit later a confirmation that they are sending me a new unit! The old one is perfectly fine except for the non element protection at the switch.

A big shout out to great customer service at Light and Motion! I've also got their Urban 550 headlight which is very impressive as well.