But design isn't what's most important. It's sound quality. And, to be honest, I didn't detect any difference at all between the two units when it came to what I was hearing on my end of the conversation. Both were equally capable of injecting my eardrum with voice that sounded crisp and clean. It's the other end of the conversation, though, where the Jawbone's $130 price tag starts to make perfect sense. The name NoiseAssassin isn't just crafty marketing slang: The technology absolutely murders background sound. To test it out, I left two voice messages for myself while sitting in front of my computer speakers with music playing at a fairly loud volume. The message left using the Plantronics headset was junk -- hopelessly inaudible. The Jawbone, on the other hand, removed the music completely, leaving only my voice. It's quite astonishing, actually (see the official demo). I also tested both headsets outdoors where sirens, car horns and wind rendered the Plantronics useless. The Jawbone worked great. In the end, this is what you're paying for. If you plan to use a headset in the silence of your office or car, then go for the Plantronics. If you plan on using it outdoors or in crowded public spaces, then there really is no choice but to spring for the noise-annihilating Jawbone.