Worst 3D experience
I saw this when it hit the states in the early 80's and it was the first modern 3D film that I got to view (unlike the old red & blue glasses). Something had to be wrong with the projector or the film was out of sync, because nobody in the theater could tell what was going on.
It also had one of the worst plots ever. Fortunately, I was able to see better 3D films, including Jaws 3D, Friday the 13th 3D, and Metalstorm. But let's face it, they were all pretty bad.