Me personally, I've given up on motorola headsets. I used the HS-850 for the longest time and was EXTREMELY happy with it.

I'm currently using the H690. This is my 2nd one. People still complain I sound like crap and audio breaks up.

I got the H15 which was supposed to be the best in audio quality, same results. Think i'm done with them.

If you are going to consider any motorola headset, I would lean more towards the H710. The H690, H12, H15, don't even bother!!!! I don't think their dual mic system is working very well. THe H721 your looking at looks like an updated version of the H710. I would give it a shot since I am somewhat happy with the H710. But if they added the dual mic system on the H721, I say forget it!

I highly recommend the Plantronics 925.