An okay time waster but nothing extraordinary

I guess for me the problem was that sometimes the hospital staff were part of his hallucinations -- such as the nurse conducting the intake survey and the doctor examining the daughter -- whereas at other times we are seeing real events.

I would have preferred a consistent approach so that we could go back and see the clues that might have tipped us off. If the movie had ended with him simply driving away we would have no idea that it was a hallucination.

Compare this to a movie like Fight Club where the entire movie stays firmly in the Narrator's mind. We don't see things from an external POV. Once you know the secret of Fight Club you can re-watch it and pick out the clues throughout that that reveal Tyler Durden's true nature.