I saw this just once, in a Sunday Matinee during the seventies. I'll gladly give it five stars, but I'll be damned if I'm going to listen to that fucking song again.
Once when I was a wee tyke there was a Godzilla marathon going on all day. This movie came up and all I remember is the smog monster flying over a crowd of people and turning them into bones and slug. I was highly disturbed after that and I couldn't watch the rest of the movie.