I have not had difficulty with two problems that other reviewers have encountered. The first reported problem is that the microphone boom lays against one's cheek and muffles the sound. This does not occur for me - and in fact I have tried to do this and it physically won't happen for me (I'm a 6'5" male). The second reported problem is with very limited range. My headset works to about 15 ft. with my Treo 700w. I have no problems at all when my phone is in my pocket or in a belt holster.The only reason I gave it 4 stars instead of 5 is that the sound quality reported by the other party is a little "muffled." Otherwise, battery life is very good, noise cancelling ok and I've had no problems linking with the Treo.