I have one. Don't really use it much because its the older model that needs the cpu on to work. Really don't to leave my desktop on to have thephone working. Believe I would use it more if I had the newer model that doesn't require the cpu to be kn to work.
As far as quality goes, it works pretty well for voip communications go. You sill notice a down grade in quality if you overwhelm the bandwith of your internet access. It took a lot for me to do that so I hardly had any issues with that. In fact, we used to be stream movies from netflix, surf the web on the laptop and also talk on mj at the same time with barely any issues.