I used to use ring of sorcery back during DotA. The main reason to use it is because it allows you to use Roots twice early. In competitive leagues, there was a limit of 1 ring per team and Keeper wasn't the most vital one to use it and you are more viable to use your other skills first. If it is vital to double Roots, get Enhanced Marchers/Ring of the Teachers (int) then as it is less repressive on your cash and the ring of the teacher builds to a Nome's Wisdom where Ring of Sorcery doesn't build to anything. In fact just a power supply is enough to fuel two roots if you use it correctly.
Each defeat brings you one step closer towards improvement.