Do not be forced to use a cable is another good point. I understand that the auxiliary jack can be difficult to access and a cable can be helpful, but like me when the plug is vertically on a dashboard, it is nice to go in order to avoid to have a Bluetooth receiver currently dangling in the void because they can put it somewhere.
Quality nothing to say except maybe a battery which discharges relatively quickly (about 4 hours of operation at about 4 days). Now I must admit that I did my testing in winter and it was very cold that could drain the battery.
Sometimes music "jump" when the battery get weak but it is very rare and the connection is getting in stride.