"Best headset, if you take the time to adjust it right"4.5 starson by barber95
Pros: The noise cancellation really works!
Cons: Tough to get the fit adjusted so that the little sensor touches my cheek.
Summary: I really like this headset. It took some twiddling at first to get the earloop bent just right, so that the voice sensor touches my cheek. Once I did that, it was easy. I don't like the ear buds that come with it, even though they have been updated from the Jawbone 2. I still use the Jabra mini gel earbuds instead.
As for the effectiveness, I did a head-to-head test with my Jawbone 2. The Prime is WAY better in the wind, and noticeably better in almost all other noisy situations as well (screaming kids, flushing toilets, etc.). NOBODY complains that they can't hear me any more - that used to happen some times with the Jawbone 2.
So, bottom line is that this thing is great if you are willing to invest the time and effort to get the fit right.