I'm not a big fan of most Plantronics BT headsets, because I feel like I should be asking you what options you would like on your Dell when wearing it.
Two coworkers had the Jabra JX-10. One said the charger connection broke within a few weeks. The other said that he quit using it because the people he called kept complaining about not being able to hear him.
I've used the Moto HS-850 for a long time, and I've recently switched to the Moto H700. The H700 is about 30% smaller, and it has a much better fit. However, I've had a few people complain about not being able to hear me very well.