After so many great reviews, I figured this would be a good choice.  It is not.  The power button is very annoying to turn on.  When using it, there is a clear buzzing noise, even when the phone is close by or in my pocket.  The switching is slow, which cuts people off and with my Treo, the voice command doesn't work.  If and was to do it again, I would NOT purchase this product.  I got two - yes TWO different headset that were defective - before Amazon sent me another to correct the mistake.  It works, but when it's not convenient to use, it's pretty much useless.