As you already know, the movie Xcalibur is about Arthur Pendragon, think Holy Grail with less jokes and better music. http://www.imdb.com/title/tt0082348/
This review http://www.lloydianaspects.co.uk/reviews/filmrev.html asserts that it is a marmite movie: people either love it or loathe it; it is impossible to be meh at this movie.
Me, I totally adore this movie, but I doubt that it is so marmite. I suspect Manchester-united-Itis. If Lindybeige guesses correct, then virtually all the votes in this poll will be top 10 Best or Worst. If I guess correct then the votes will be randomly distributed.
I used to be meh about Manchester united Football club until I met a rabid MU fan who went on and on and on about his favourite team, so now, I hates it forever. I'm guessing Lloyd, an enthusiastic Xcalibur fan, went on and on and made the people he knows hate the movie.

