I've had a great deal of trouble finding an adequate handsfree device to comply with the new laws in CA regarding cell phone use while driving.  With some (such as the Motorola H700), the mic would be right up against my chubby cheeks and people couldn't hear me, and with the speaker just resting outside of the ear, I often couldn't hear them either.  With others, such as the Jabra that clips to your car's visor, the road noise on the freeway made it impossible to hear the other person, or for them to hear you.  The Plantronics 220 has been a nice change...  It actually fits my ear and face, and I can hear and be heard with no trouble.  I can lean forward without it falling off/out of my ear.  The unit does get a little staticky at times, which is why I didn't give it 5 stars.  My husband and I both have this one now, and it's definitely the best bang-for-your-buck headset we've tried yet.