So I went into this movie expecting it to be the opposite of what it was. For whatever reason I was under the impression that the main character was going to find himself in the actual world of Don Quixote, accidentally killing him and having to take his place for the duration of the movie. Hijinks ensue. Pleasantly surprised that that's not the case.
I think the biggest criticism I have is one already brought up by Xeybozn, which was also my main criticism from In Bruges earlier on, is that once 'Don Quixote' and 'Sancho' are nowhere to be found in a scene I just kind of lose interest.