I have the KA 5qt. I like it, but I have had some problems with it.
I have carpal tunnel really bad, so mixing with a hand mixer was getting painful, so I invested in the KA 5qt a couple of years ago. Shortly after the 6 month warranty was up, I was mixing egg whites on high speed one day and the thing backfired!!
Sparks came out the back end and it stopped working. I unplugged it so it would start anything on fire and let it sit for several minutes. When I plugged it back in and turned it on, it still worked, but it will not go above a 6 speed. You can push it all the way to 10, but it still goes the same speed as it does on 6.
I contacted KA and they told me that since the 6 month warranty was up there wasnt anything they could do for me, but they could send me a coupon for a new KA stand mixer.
I contacted the store I bought it from but they said to contact KA. So i was essientially stuck with this mixer. I still have it, I still use it all the time, but for all the money that I spent for this thing I wish it would have been made a little better, since I heard nothing but good things about them.
Moral of the story: The old gray mare just aint what she used to be. And that can be said for a lot of products these days.