Like so many others, I am on a perpeptual search for the "perfect" Bluetooth headset. I want it to slip over my ear quickly, to fit firmly into my ear canal, allow me to hear clearly while I am standing in the midst of a roaring crowd and reproduce my voice perfectly no matter how lousy my connection.Someone on quest like this encounters a lot of disappointment.The Jabra 510 met some of these requirements, but not the critical ones. Hearing the other party often required pressing it into my ear and I often received complaints that I was difficult to hear.Many reviews on the Jawbone have been glowing . . . and some have been downright derogatory. I figured that I might as well try it.The design is visually appealing, but the earband is a piece of bad design. Apparently made of aluminum or some metal alloy, it is relatively inflexible and difficult to place over the ear. One point against. There have also been reports that these earloops are easy to break.There are only two buttons, both of which are hidden. One is relatively easy to find, the other requires a bit of hunting. This second button is also the volume control. Press it a bit too long and you've just turned off Bluetooth and lost your call.The visual indicators for status are sparse, so often you are left guessing as to precisely what status your Jawbone is in. I found that restablishing my Bluetooth connection, which I had accidentally severed, was way more difficult than it had to be.Initial pairing was flawlessly simple, but if you lose your connection while driving on an expressway, for example, trying to reconnect turns you into an accident waiting to happen.Received audio quality is pretty good. Using the standard ear bud, the fit was good, but not perfect. The volume control proved to be hit-or-miss. Sometimes pressing it as the directions specified increased the volume. Sometimes it broke my Bluetooth connection.I tested the voice transmission capability by turning up the television and radio at the same time and calling my own voicemail. I must tell you, the noise cancelling technology works very well. Voice quality is acceptable: we're talking cell phone audio here, not concert hall acoustics.The battery seems to last the specified times, but the proprietary charger connections are not only a bad idea, but stupid as well. While one end of the cable can be plugged into a standard USB slot, the end that attaches to the Jawbone is proprietary. This is just plain dumb. It should be a mini-USB. Instead you have to remember to pack yet one more cable.Is the Jawbone worth the premium price? Kind of doubtful. With other headsets, I've never been unable to complete a phone call, although sometimes I have had a hard time hearing and being understood. The Jawbone does make your voice more intelligible with its noise cancelling abilities. So I guess the determination would be how often you would need to depend on that noise cancelling technology. I am also wary of Aliph's customer support. Many Amazon reviews have remarked on poor build quality, breakage and very poor customer support by the manufacturer.Jerry