I originally bought the HS820 headset thru Amazon last Xmas along with a Moto DC600 wireless adapter to use with my T720. I quit using it after about a month, because the ADAPTER killed even my extended-life battery before I got home from work. In July, I bought a Motorola E815. Pulled the headset out of the drawer, and have been happy with it ever since. It works great with all the E815 features. I won't ever go back to a wired headset, EVER. The only caveat is that I wished the volume went up just a bit louder. My car is a little noisy, and sometimes I have some difficulty hearing folks on the other end...