I'm not sure I can write a useful review about this, because I can't really write about this anime objectively. The reason for this is that this one is my all-time-favourite anime for many reasons.
The story is perfect but actually the characters make it interesting. All of the characters all really well-thought and unique. I'm also addicted to the first opening song which is the debut song of the Black Stones.
That's it. Like I said, this may not be helpful to you but I can tell you one thing. If you like rock music, style, romance, surprising character development, and first of all stories about friendships, you'll love this. I love it. It's a shame that Ai Yazawa couldn't finish the manga.