This is, in my very humble opinion, Terry Gilliam's best film, but still it falls short of the mark. I really liked the film as it exists in Gilliam's cut (there are two other edits released, and his is 142 minutes long).
The story is compelling, but Gilliam, as is so often the case, gets bogged down in special effects that add nothing to the story. The fantasy scenes of our hero (Sam Lowry played by Jonathon Pryce) are very effective, giving us insight into Lowry's character. But the loss of Harry Tuttle in the paper creates confusion, and the samurai doesn't tell us anything we don't already know.
In spite of its shortcomings, I really liked the film. When it's intentionally bogged down in bureaucracy, it's both telling and funny. There are great comments on the superficiality of society and the dangers of trusting the bureaucracy. Although I don't call it a success, it does not fail (as "The Adventures of Baron Munchausen" does).