This is not so much a review as it is a service announcement. If you have watched the anime you can skip to book 10. 1-9 are more or less the same as the two first seasons of the anime, with a few small non-important changes. vol. 10 is alot like the anime but it sets up vol 11 which is not adapted into the anime.
Would I recommend reading vol 10 and 11? YES! It shows great growth between many of the characters and is a great small storyline that any fan of the anime would enjoy.
The reason I only give the manga a 5 is because the story is incomplete. It may be completed in the light novels but the manga on its own will nit give the full story and that pulls it down alot. Had it been completed I would most likely give it a 7 perhaps an 8 if the story improves.
All in all you should be able to blast through the entire manga in a day if you focus on it, and it will be entertaining, the art is good, but if you have seen the anime just skip to vol 10 and enjoy.
I have not read the light novel so I don't know if vol 11 is a manga-only but I would think it is also in the novel.