I like my Light & Motion 550 but I don't think it will stay on a nearly as long as advertised. I think L & M, like so many other manufacturers of battery-powered devices, has seized on the most optimistic run-time figures possible. For me, after a couple year's of use, battery performance is probably 70% of original capacity.

Pros: Compact design and quick release strap make it easy to put on and take off. Weather resistant design that works. Charge indicator led tells you charge level of the battery using different colors. Micro USB charging.

Cons: Expensive (but it currently sells for far less than $180), gets hot when charging, and battery life tapers off steadily from a full charge that is fairly limited to begin with.