The live action nailed it!
Sure there are some cut scenes from the anime but the important details were not left out. The whole movie can stand alone and even those who haven't seen the anime yet could surely understand the whole plot.
The characters' acting are spot on. Takeru Satoh's (Nagai) portrayal is effortless. It is so natural and convincing. Sure, there are times when I wished he'd say "amakakeru ryu no hirameki" but that is only because I was so affected by Gou Ayano's (Sato) acting as a villain I wanted him to be dead for sure but this is Ajin; Die and be alive. Gou wcompleted the ambiance of the movie.
To sum it up, everything, from characters to the plot were all stitched perfectly I could not ask for a better adaptation.