I had a phone that had terrible BT reception so I purchased 3 other earpieces; the most expensive of these costing $129.  I went to a forum to see what others have done about this problem when I found out about the Voyager 510.  I must admit, this is the best BT on the market BY FAR.  It is truly comfortable, not just "claimed" to be.  I am on the phone quite a bit, and I have never run the battery down, the volume can be turned up louder than any of the other, and plugging the unit is easier than most of the others. This is a great unit.