Plantronics' most deluxe monaural Bluetooth headset marketed towards iPhone users is the Discovery 665 ($150), which uses the Bluetooth 2.0 wireless standard, a Lithium-Ion battery, and two included chargers to offer you the ability to take iPhone telephone calls from up to 33 feet away from the phone itself. Weighing 9 grams -- half the weight of the Voyager 520 and many other headsets, but not as lightweight or small as Argard's M10 -- the Discovery…
