I didn't like Grave of the Fireflies that much, really, but I downloaded this just out of interest because I have never seen an AMV done to that anime before. I've never heard of the band, but the song wasn't bad, actually.
On the video itself, I found it a bit boring, really. Maybe it's just that I'm not a fan of the anime, or the band, but I think this could have been more emotional than it was. Your clip selection is ok, but it didn't really give enough credit for the powerful emotional affect the movie had. Maybe if it was done in a more chronological order, it would have been better?
I liked those effects you used on a few parts of your vid. Those bright bars, I mean. They hit the beats nicely and looked quite nice

However, your syncing was decent. Although sometimes I couldn't see whther you were trying to sync to the lyrics or the beats, which was distracting. But overall, nice sync
