God, this was a confusing film to watch. I have never watched the Slayers anime series, but I have a feeling it's not necessary to have knowledge of the series to understand this film.
I watched the English dub of this film and it wasn't that bad. Except a handful of voices were just . . . annoying. The music and the animation were awesome. The only problem was the story. It was slow to make progress into the main plot, but there were a lot of no-nonsense scenes in the film.
Plus the villain kind of sucked, IMO.
But if you like fanservice, girls with large chests (and a young sorceress who wishes for a large chest), and good animation from Japan, check this movie out. But be warned: You might have to rewatch the movie a couple of times to get the plotline.
My rating: 2.5 stars