Last authum I did get my Plantronics
This has been one of the best headset I ever used. Both as a UC headset and a mobile headset.
Lot's of my customers has also used this and they are as I very happy about it.
It's simple and great quality, long hours of speaking and together with Plantronics HUB witch you can download here: http://www.plantronics.com/us/product/plantronics-hub-desktop
You can from this application control and update firmware and other functions as well.