As stylish as the Jabra is, in the slightest wind, it's worthless. Since I walk more than I drive these days, I needed one that people coudl actually hear me on the streets of San Francisco. I settled on the Plantronics Voyager 510, after reading great reviews of it's real-world performance. The biggest improvement is a windscreen on the microphone; that alone is really all I wanted for the Jabra. Sure, the Plantronics is more functionally elegant, but no one just sells these windscreens! What a racket.
In any case, it's working well so far, with good comfort, and very good audible cues to tell you what's going on. More as I discover it with the Sony Ericsson Z520a, my fairly new cell.