The company I work for has a couple of the ear mounted versions. They’re designed primarily for aerobic intructors. We recently rented them to a Yoga shoot, and they were just what the Doctor ordered. Cheap, super small, and so far reliable. I agree with Mr. Scharton though that the built-in rechargeable battery could be a problem when it finally gives up the ghost.
Hadn’t heard of this site, before. I’ve added it to my “follow” list…….