Looking at the detergent cup in this machine makes me think of how much better GE's plastics were even in these years compared to the plastics from whomever that were used in those fragile detergent cups in the WP top loading portable dishwashers. Maytag's plastics were never all that great. The white buttons on their 06 series washers oxidized and discolored at various rates, even when replaced with new ones.
I have to put in my two cents for the performance of the bow tie impeller GE dishwashers. Not only did the stainless steel impeller help to pulverize food, it also resisted the dulling of the edges seen in the Bakelite impellers. Another major factor in the performance of these machines was the reversing motor and the necessary pause before the change in direction which allowed the soil to settle out of the water before the pump out, something not possible in the models where the timer ran off the main motor. This feature gave better disposal of solid food particles.