Firstly I want to thank user inzaratha for recommending "Kono Oto Tomare!" to those who are reading "Chihayafuru!". If not her, I might have missed this gem.
The story in this manga is great. Its premise is unoriginal, but the way it's being told and the pacing makes it highly enjoyable to read. It has some funny moments, some touching moments, and some sad and romantic moments. I've read 17 chapters at the moment and there wasn't a single one that didn't serve purpose or was boring in any way.
I give the story a 9.
One of the main strengths of "Kono Oto Tomare!" is the art. If not for the art, many moments wouldn't have the same emotional impact. It's really hard to describe it with words, it's better to see it for yourselves.
I give art a 10.
I really love characters in "Kono Oto Tomare!". They are very likable and interesting.
There are three main characters:
Kudou Chika - a bully and an outcast with a tragic past. Everyone fears him, but he is strong, honest, determined and really cares for his friends.
Kurata Takezou aka Four Eyes - Koto club president and the only member of the club at the beginning of the story. He is good and diligent person, but he lacks confidence.
Hozuki Satowa - One of the most beautiful girls I have seen in manga or anime. The young prodigy of the koto world. Because of her talent she is very lonely and don't have any friends.
The whole cast has a great chemistry but the chemistry between Chika and Satowa is something else. First time since "Dengeki Daisy" that I've enjoyed the interactions between two leads this much.
Characters 9.
I'm having a great time with this manga, I've read all 17 chapters in a single breath.
Enjoyment 10.
Overall I highly recommend this manga to people who like interesting personal stories with great characters and art. The only flaw "Kono Oto Tomare!" has that it's only 17 chapters long at the moment, and you'll be craving for more.
And as of final score - manga that had me on the verge of tears several times can't get anything less than 10 from me.