I'll be honest here. Even tho GDW is newer than GNG I still think that GNG is animated better. I think you all have seen those GDW animation fail pics and if you haven't you really should check some out. First few episodes are well made but then in some point it seems that animating gets a bit different. I can't really explain it so you should really see it by yourself. GNG and GDW share some same characters like Akame,Smith and John. Even tho I didn't like animating at some points the story is emotional and just simply awesome. I know GDW has kinda like same plotas GNG but tyrannical bear was just changed to huge dog.

I've watched this anime many times and I own the completed series box but anyway I prefer manga version and GDW manga story actully goes further than anime.