So far I've only tried the LG Tone, which gets great reviews on Amazon, but either I got a defective unit or my expectations are too high. The sound quality is fine for music/audiobooks, but the call quality is abysmal. People sound sort of echo-y, there's a clattering/static sound in the background, everyone complains that my microphone volume is too low no matter how I adjust, and any type of wind makes me completely inaudible. Also on my third call, the headset started lagging everything I said by several seconds. Even in my own apartment with no background noise to speak of, my call contacts were complaining about the headset and how they couldn't hear me. I'm using it with my iPhone 4. While I want it to be stereo, call quality really is the most important thing for me as I am always on the phone walking to and from work, at home on skype, etc. ETA: Bah, I guess I'm going to have to settle for a mono bluetooth headset. Looking at the Icon HD or the Blueant Q2, and a couple others. Hopefully I can find one that works well.