I just had a 6 qt KA die on me the other day. As the old saying goes, I don’t think they make them like they used to! I have a 4 qt refurb that I have had for at least 15 years and it still runs like new. I was looking at the 7 qt pro model that Williams Sonoma offers, but $550 is a lot for a brand I am quickly losing confidence in.
I can tell you that powdered sugar WILL get inside the head unit and can eventually coat the electrical contacts. If your unit just won’t turn on anymore, unplug, take the head off and blow the insides good with canned air / airbrush compressor.