I had no idea before watching that this also existed as a manga series and an anime series. Nana tells the story of two girls with the same name meeting and forming an unlikely friendship. The two central characters (Nana and Nana) are very different but they compliment each other well. The acting was good throughout, and the characters believable. I enjoy watching movies about music, though I didn't really consider what the band played as "punk" here.
I'll definitely be on the look out for the manga series in the future. Plus there is the sequel, but since two of the central characters have different actors in it I'll be wary of it.
8/10