Cooper Hoffman is good, Mark Hamill is virtually unrecognizable, and David Jonsson is extraordinary. I predict his career will skyrocket following this role.
As for the film, I really wanted to like it. I suppose I would have, if not for the motion sickness I experienced, plus the non-stop jabbering these teens do! Insane. No boy talks that much, and surely not while walking for his life.
The characters walking more than 300 miles nonstop is wildly unrealistic given the fact that even trained endurance walkers rarely exceed 50–100 miles in 24 hours, much less in socks alone for the final 100.
Crazy.
If you go, take Dramamine and wear earplugs. That's my advice on the matter.