It appears that I have some semi-professional value I can add to this product given my experience with bone conduction and communications equipment/electro-magnetic spectrum. My battalion switched a lot of our fire teams to bone conductive earphones and later to a suite of personnel communication equipment which could utilize low-energy personal area networks (with a fallback to wired interconnection).
I applaud that some product lines among companies making BT headsets, heaphones, earbuds, earphones have really made strides in fidelity, and that we are seeing more of these devices also leverage the aural characteristics of our skull other than our outer ear. There are some misconceptions I believe the marketplace has failed to quiet which could be wear some customers non-fit-based criticisms arise.
These BCRs (bone conductive receiver) are what I expected from a civilian adaptation of the device. I purchased these to end up being used by spouse given her hatred of what she calls unnecessary wires.
(1) Fit for her head is pretty good especially the absence of strong pressure at the contact points. These have I would say average flex which should help with some fit, but not all circumference/fit issues.
(2) Battery life is good compared to the weight of the headset with charging time being what I expected.
(3) Quality is on par with what I was using in the military 5-6 years ago which is about where I expected low-cost products in the consumer market to be at currently. These can be used for music, but imo we are still a few years away from entry level hi-fi wireless over low-power radio networks such as BT. Using this between talk radio, podcasts, and some voice communication is where you will see this product more fulfill your expectations.
(4) Durability I will have to get back to you, but I expect it to handle normal wear and tear outside of forceful drops and regularly sitting on it.
Hope everyone who isn't completely satisfied can work out amiable but rational arrangements with MD and the manufacturer. Lately I've seen some very good customer relations come out of the MD team which did surprise me, so work with them and be patient. I believe the product has been delivered as advertised albeit in the future having a little more explanation concerning wear and fit might be useful for those who haven't utilized bond conductive technologies in their past.