I just saw this movie in the theaters yesterday. It is really good, maybe the best movie I ever saw. I'm not really into giant robot shows in general, so it's funny that a couple of my favorite movies and animes are both giant robot shows.
They claim they tried to make an original show, but I think Pacific Rim copied the anime Godannar exactly. Everything is exactly the same as Godannar. The only difference is that Godannar had more girls in it.