Pros: good fit, nice looking, filters out background noise so the folks on the other end hear you (and just you)
Cons: sometimes sounds a bit tingy on your end
Over the last six months, I've had three different Bluetooth headsets. The first two were pretty cheap and had just okay sound quality. But the worst things about them were that: a) people couldn't always understand what I was saying; b) the voice recognition didn't work very well and I'd end up having to go through my phone book manually to get the right person; c) even when I got the right person with the voice recognition, no matter how loudly or clearly I spoke, sometimes the damn things wouldn't understand "yes" or "no" to actually place the call; and d) the person on the other end could hear all the background noise as if they were standing right next to me.
And now that I've thoroughly complained about the last two....let me tell you the Aliph Jawbone is like a dream in comparison (for the most part, anyway). Let's start out with the basics. First, it's actually pretty comfortable. It's taken me a little while to figure out which earbud is the right one for me but I really like the fact that it comes with a few different choices for the ear piece and the earbud. It definitely allows you to customize the fit, since one ear is not necessarily like the other. And the headset is pretty sleek looking and it's a good size. Not too huge, not too small. A solid Goldilocks just-right. (And the presentation in the packaging is pretty hot too, so if you're gifting it...it's very nice looking.)
The sound quality through the headset is pretty good. It doesn't sound exactly like the way the audio comes through the handset and on occasion there's a bit of tingy sound...but overall, it's not bad and I do like that the volume adjusts to your surroundings.
I think my favorite part about the Jawbone is what the person on the other end hears. The first day I used the Jawbone I did a test with my sister. I called her using the Jawbone and stood next to my iPod dock speakers. I incrementally increased the volume while I talked to her and kept asking if she could hear the music. At the loudest, she said she could hear it a little bit - but not much at all. Definitely an improvement over the last one where a friend of mine said it sounded like she was "in my ear" while we were on the phone.