I have been using this tool for several years now, mostly as an employee but also in my personal capacity (as of late).
The interface is very easy-to use and intuitive which makes even complex tasks like rating skills seem simple! It's almost too good at what they do; sometimes you wonder if there are any flaws or room for improvement? Not really anything that stands out specifically other than maybe more options/features would be nice - perhaps some kind customization features could help solve issues where users may not know how exactly their ratings will look when viewing by others. This has helped me get better insights into who needs constructive criticism most effectively so we can address our weaknesses sooner rather then later.