The earpiece is pretty comfortable and the sound is good. The microphone is what will have you and the other party thanking Plantronics. Ever talk to somebody who is using a cheap or small cellular phone? Annoying isn't it. The M145 warms things up, no more speaker phone sound quality.I always use the headset in the car. It's great on the home phone too. When they start putting headphone jacks on all the home phones everybody will have a headset. They are so comfortable and convenient, now I have two.(car/home)The only thing missing is an on cord/headset answer button.(might not be possible for a universal product) The volume control is nice but I rarely use it, would trade it in a heartbeat for an anwer button.Last thing, those headsets that have a mic that clips to your lapel are ok, maybe a little more discrete. Your voice won't sound as warm because the mic is farther away.