Saw the movie on Sunday.
As for a Horror version of I Am Legend I thought it was similar to that.
You don't know what's in the dark, less is more tourists get killed but you don't see their deaths with the exception of 2, don't see the humans altered by the radiation clearly until the end but it's not that long, somber what is help isn't help, and a somber ending.
I would reccomend it.