Just finished watching it, Overall, It gets the mood of UBW quite well. I thoroughly enjoyed it.
Obviously its not in as much detail as the VN, but I would say its respectable that it managed to convey UBW in less than 2 hours. This is definitly not a replacement of actually playing the VN, as I don't think anyone who hasn't played FS/N will get any of what is actually happening during the movie.