I have had the jawbone for a week and this is what I think.Oh, wow. If you want the entire world to know you're on a blue tooth, buy this one. I made sure to buy the black so it would have a subtle appearance and boy was I fooling myself. Definitely one of the largest blue tooth I have ever seen.As far as the functionality, I did not see a difference with sound quality on my end and not with that of other's ability to hear me. I was having the same exact problems with people hearing me that I did with my previous blue tooth. This was in my car with music or with the window down. If I at least found that benefit to work I would have considered keeping it. But I am returning it today because of the massive size, unnoticed noise reduction, the constant disconnection with my phone(TREO 755) and that I find the alert sound and ringing tone unbelievably annoying.Every time it disconnects with my phone (which is very often) there is a loud three beep sequence in my ear and then it repeats once it reconnects. Then I would like to know, please someone tell me, who choose the tone that plays when the phone is ringing. It is the exact sound that plays in scary movies right before someone gets killed. Unfortunately, coupled with everything else I don't like about it, this was just the cherry on top. I am returning it today.No thank you. It's just not for me.