I believe the 18 series to be the best KitchenAids made. Some sort of insanity hit after the 18s. Dishwashers, as they are currently constructed under the strictures of the energy bonobos, have no way of purging cold or cooled water from the hot water lines. If you run hot water to the machine before starting it, you need to keep the water moving through the supply pipes at fairly short intervals to keep it from losing too much heat between fills unless your dishwasher is very close to the water heater. The 18 Superba did this beautifully; two fills with short circulation periods to use the hot water to warm up the machine, then the first wash. To compensate for heat loss in the pipes during the first wash, the second wash was heated. The first rinse cleared the lines of cooled water allowing the 2nd and 3rd rinses to use hot incoming water. After the 18s, the machines spent time doing static heating of the first fill, which was then thrown over the room temperature dishes, losing almost all of the heat of the incoming water. In the meantime, the water sitting in the pipes lost heat for the next fill which was not heated to a guaranteed temperature. They added time to the cycle, but wasted the time and energy. And eliminating the Constant Rinse after the 18s to save water did not help the washing performance. Not that I care anymore, but it would be interesting to have known what they were thinking. I guess we do know what they were thinking because we can see what dishwashers have become. What a world. What a world.