I went to see a Q&A showing of this last night and it's pretty enjoyable.
I don't think anything Ben's done since Kill List has really lived up that film and this certainly doesn't either, but there's enough good lines and a generally humorous tone that just about carries it through its compact running time.
After seeing the trailer I thought the shootout was just the set up to the wider film but that is actually the whole film.
In the Q&A afterwards Ben said they got through around 7,000 rounds of ammo, so that should tell you how kinetic and nonstop the action is.
I'd recommend it but it's a bit slight overall.
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