I had/have a KitchenAid (20 years old model, all metal). I 'upgraded' to the Bosch Universal. It is awesome!
http://www.amazon.com/Bosch-Universal-Plus-Kitchen-Machine/dp/B0016KU16G
Of course, I just reread about the Kohl's cash, can't help you there! The Bosch does make a whiring sound, but it has a powerful motor. It's not annoying, just what you would expect!
I would go with the pro 600. It has metal gears.