I posted this on the Bosch thread, but it's also applicable here.
Using the stainless steel bowl with the hooks on the bottom makes a huge huge difference with the Bosch. I bought a Bosch about six months ago and was quite unhappy with the way it performed with the center column bowl. So I bought a used ss bowl on eBay and am quite happy with the way it works now with the hooks on the bottom. I had a KA before, and I still prefer the way it kneads, and it's certainly better for small batches. But I can now make six dough balls of 20 ounces apiece at one time in the Bosch, which I would never have been able to do in the KA. It's also nice that the Bosch has suction cups on the bottom and doesn't walk all over the counter, like the KA does. So I can start it and go do other things. Most importantly, it's nice that I don't have to worry as much about burning out the engine or the worm gear, which is what happened with my KA after a few too many heavy doughs, and is what reportedly happens to almost every KA eventually if you make a lot of bread and pizza.
I read the Cooks Illustrated review and found it interesting but flawed. It gave the Bosch a poor review, but, crucially, they didn't take into account that (1) the Bosch works much better with the stainless steel bowl, (2) it works better if you make big batches and there's really no reason not to, since you can always freeze the unusued portion, and (3) the Bosch probably won't burn out like the KAs will. So while the KA might perform better for a brief product review test, it sucks to have to install a new worm gear, or even buy a new motor, every few years.