I bought this product about 1.5 years ago at the advice of a friend. The sound in and out of it is very good, BUT the on/off button is too small and tricky to use, you need fingernails to operate.NOW here's the REAL problem-the bluish/grey rubber that covers one side of the unit that goes behind the ear and covers the wiring that goes down to the boom starts to disintegrate after about 6 months to a year later and just gets worse as time goes on. It will start to crumble and break up leaving you with just a wire going to the boom. I don't know if Plantronics uses this rubber on their other units but if they do they will do the same thing.PLANTRONICS, BUILD A BETTER PRODUCT!