Amusing in the dumbest way, nowhere near as clever or as biting about Hollywood as it wants to be, yet somehow strangely likeable. If Whedon's Much Ado is what he and his mates get up to while mucking about with cameras at his home, you get the sense this is what Rogan and his pals do in the same circumstances, OTT CGI and Michael Cera aside.
Horribly disjointed, and feeling more like an extended (fictional) travelogue than any kind of quest for survival. The famously troubled third act felt like a rejected script for Torchwood stapled awkwardly at the back of the original screenplay, while the lack of even a basic attempt to provide characterisation to anyone outside Brad Pitt makes the whole thing disengaging and lacking in any sense of peril.
Still, at least Glasgow looked nice...