Unless reluctant to headsets or earpieces to call, that was my case before - but I think it becomes dangerous over time - this little device is quite great. I use it for several days quite intensively, even without having to recharge. I am amazed and pleasantly surprised because for me a good autonomy is crucial. It seems that the sound is a little muffled - I use this device as a single handset - but when I ask my correspondents, they tell me they hear me very clearly. And what a pleasure not to have my big smartphone in hand! Device also very helpful to be informed of the mails and sms we receive - I set to be notified only sms - I consider that the real plus is the independent radio RDS feature. Yesterday I walked over an hour in the city listening to the radio without any interruption, the sound was crystalline. I agree without problems club of five stars.