I bought the H710 in August 2008.  It worked flawlessly for about ten months, then suddenly, the microphone stopped working.  At first, it was intermittent, sometimes people would say they couldn't hear me, other times, no problem.  Then one day, dead on all calls.  Sent it back to Motorola for a warranty exchange in July 2009.  It's January now.  Guess what, the replacement is doing the same thing.  I love the feel and operation of this headset; it works especially well with my hearing aids, but if the other folks cannot hear me, it is a piece of garbage.  FWIW, I also hate the proprietary charger.  I'd be interested to know if anyone has any LONG TERM success with this headset.