This is a great idea of a film, a futuristic theme park full of robots. Its such a good idea it has been homaged/parodied in everything. The casting is brilliant, James Brolin just spilling full of charm and Yul Brynner is pure menace as the robot that won't go away. It doesn't even kick into full gear until 2/3rds of the way through it, but that is obviously its way of lulling the audience into a false sense of security. Unfortunately, like many trailers today, the trailer for this reveals all the twists hence making the beginning a bit of bore as it goes through the motions at a languid pace.
The good points, as I do like this film, are that once it gets into what its wanted to be doing from the start is effectively done. The stunt work is fantastic and the effects are cool. The remake that is in the works has a major problem in that they need Yul Brynner, he makes the film.