More functionnalities than with other comments system : for example you can give a color to the frame of your comment, can pin it, hide, etc
Ease of use
Very easy to set up and to use for you and your users. There is good documentation and support
Support was always fast and answered all of my problems with clarity and positive attitude.
The extension is really easy to use so I did not use the documentation but it is present and may help you if needed.
Value for money
Good pricing and even better if you take a package with their other components.