See it if You want a truly odd story with very dry humor and an anti hero protagonist. Great acting and staging.
Don't see it if It gets slow at times and is quirky enough to throw you if you don't go with it. If you don't like Will Eno's work don't see it.
See it if you like cerebral theater; Eno's script is filled w zingers/insights. Gnit looks for selfhood all over, but by looking, he's lost it.
Don't see it if you want a tight script, GNIT wanders like its char. The action can get wearing. Still, funny/thought-provoking. Pitfalls of selfishness.