This movie is cute, fun, emotional... and predictable.
The rivalry between the western and eastern style music students, exacerbated by the incompetent staff, is a good foundation for the story. The individual characters are enjoyable, especially the 2nd Dimension group; straight out of a manga and well-portrayed. I especially enjoyed the character that didn't have a line in the whole movie, but played one of the main supportive parts.
The movie fell apart for me a bit near the end. It started with the well-known separated-by-bars competition that is shown on YouTube (which I imagine is what brings most people to watch this movie). To be honest, I didn't see a clear distinction of a "winner" there; both sides did equally well. So that bit of directing started somewhat of a downhill slide. Add to it that I could think of a far better, more cooperative end musical presentation that was more in line with the overall theme, and well, there was room for improvement. But that's okay.
I didn't mind the fanciful holographic projections in the performance, because the Chinese and Japanese are masters at mid-air holographic technology, projecting 30 foot Vocaloids in the middle of a crowd or having tigers running down the middle of a shopping mall. However, it was unnecessary, was a bit jump-the-shark, and the addition of two very-out-of-place electric guitars to the mix just pushed it that much farther... which is why I gave this 8 stars rather than 10. It was a good movie; the director just went off track a bit in the last 15 minutes or so. The focus should have remained on blending Eastern instruments and music down to the very end... and perhaps even blending the two methods into a harmonious whole. But bringing in two overdrive electric guitars out of nowhere into a traditional orchestra did not well-accomplish that concept.
So overall, a good movie that could have had a better final presentation. If someone wanted to be critical and focus on flaws they would have valid reason to do so-- if we're to take a manga-movie all that seriously. But as it stands it is well worth watching and enjoyable overall. Probably wouldn't mind watching it again, which for me is high praise for any movie.