Yeah.... Just finished watching this one.
Story: I loved it. But honestly.... it wasn't the most waterproof plot considering logic. They sure have much time to think about literally everything else but playing the piano - while playing it. Espacially, since they tried so hard to learn the notes etc. That aside, it was intriguing and DAMN was it emotional! Almost shed a tear there.
Animation: Beatiful. Really. But what is it with those lips? Background art not consistently but most of the time fantastic.
Sound: Yeah, someone sure loved Chopin. There are so many different styles and artists, great composers with beatiful works. But they seemed to pick just a few. That aside, it was very good.
Characters: A little bit too convenient. But individually beatifully crafted chars.
Overall: I is definately not a feel-good-show. But a must-watch nonetheless.