The sound of these Motorola S9 bluetooth earphones is pretty good... when it's working that is. I had numerous connection problems, but that's primarily due to the bluetooth stack in my laptop, not the earphones. I was able to successfully pair them with my cell phone and laptop most of the time. The stereo sound is good, comparable to wired headphones.My biggest complaint, which may ultimately lead me to return them, is the physical fit hurts my ears. I'm 6'4, 205lbs and have the smallest ear adapters (of the three that come with the S9) on the earphones and they still feel very large in my ear. I suppose they do this so that the fit is snug enough to get the earphones to stay on while working out. However, after 15-20 minutes, my ears really start to ache and I have to remove the headphones for a while. I use them mostly at work, sitting at a desk, to listen to internet radio.