I purchased 2 of these wireless handsets for my staff after using one for a year. The sound quality is excellent for both ends. The headset is, despite it's larger size, surprizingly lightweight and unobtrusive. The range and battery life are excellent as well. I have used it up to 40 feet away from the base station with little to no interference. The headset comes with several earbud covers and the mic can be rotated and swiveled. The mic's length cannot be adjusted, but that is a minor complaint. The headset includes controls for adjusting call volume as well as a button for answering calls.My staff (an IT department) loves these units and uses them daily. I have a total of 4 of them in my department and have had no interference or interoperability issues. I plan on purchasing more in the future.Originally the price for these units was pretty high (above $250). The price on these units is very reasonable now and completely worth it.We use an Allworx VOIP phone system and these units integrate with the handsets (9212 and 9224) seamlessly, the additional handset lifter is not required for these handsets.