I would definitely not recommend the mid-range of KitchenAid. The silly thing is definitely quiet but we have had nothing but issues with it since it was purchased. Brain was replaced at least once. Now when it gets cranky we have to re-set the circuit breaker for that appliance before it will start again.
It does have a 'food disposer' incorporated so no pre-washing needed per se. It takes forever to complete a cycle but I think that is the norm now since everything is 'low water usage'. It gets dishes clean but we also have very hard water so have inherent problems due to that issue.
Our dealer - like illinois' - also recommended to run the tap water until it is at it's hottest before starting dishwasher as well for the same reasons.