In the last several months, I have seen FREE RADICALS, A COLOUR BOX, HARPYA and now ALLEGRETTO--all animated shorts that have won many awards and are, in a way, all exactly alike. All feature music (often classical or swing) and various colors and shapes bounce across the screen in perfect rhythm to the music. While all of these are well done, they also are very repetitive and I frankly am going to avoid these types of films in the future--even though I usually have a high tolerance for art films.
Now in ALLEGRETTO's defense, I should point out that it did come before two of the movies lists. However, in 1935, A COLOUR BOX appeared and was probably the best of these films. With ALLEGRETTO coming out only a year later, it does lack originality.
My advice is that if you haven't seen any of these films, by all means try ALLEGRETTO. Just understand that a human being can't live on a steady diet of these sort of pictures.