It works fine once you have it on.It's a hassel to put it on, keep it on, put it away etc.The length of the left ear cord is unbelievably short and the other one too long.It gets tangled very easily and the sponges on the ear buds come off easily.Once you have it on it works great. The sound quality is pretty good and the person on the other end is able to hear me loud and clear with no static or echo.One more thing that I noticed is that the normal mic and earphone on my Treo 650 stopped working. Which I suspect is more of a Treo 650 issue manifested by the headset.