the cheap ones suck, to be sure.

Break down and buy a mid-range Bosch or a Miele and they work like a champ. The Miele’s even heat their own water and can be plumbed to cold water only for their inlet water and then they heat it to the needed temp for the load. The key to getting modern dishwashers to work is high temp water either produced on their own or supplied from your tank. If the water at your sink takes forever to get hot, then put a circulating pump on your hot water system or buy a Miele and set your hot water heater up to 150 degrees.