I saw this movie at the DuPage Theater in Lombard IL. It was one of those magical little theaters that had a thin veneer of of paint (and lights in the ceiling to simulate stars) that made you feel like you were whisked away to a foreign destination.
This was a part of some very magical summers, as my cousin and I could hook up on the Elevated Trains (The L) and get almost anywhere in the Chicago area.
We saw JTGK and loved it from end to end. As an adult I can look back and judge the sophistication of the "Clamation" and rate this movie pretty poor. How could this movie be compared to any film touched by Ray Harryhausen. The answer is simple, it can't be touched. It is no longer economically feasible to do clay modeling. CGI now rules the day. But from 1949 to 19891 Harryhousen produced one amazing film after another.
It is true JTGK was a poor imitation. However, from the perspective of a 10 year old, it was awesome. I loved this movie and would try to see it when ever possible. It was a regular in the summer movie matinee's in the 60's.
Oh and if you do not know, the movie is being remade using CGI. The release is for 2012