I would go KA based on price and the clicking sound the Thermador makes on the simmer setting as it cycles the igniting and extinguishing of the flame over and over and over....

Hope this helps!

The Thermador clicks on extralow simmer of 375 btu/100 degrees. KA only goes down to 650 btu on simmer. If you raise the Thermador simmer to 650 btu it no longer clicks.

KA had ovens with self clean problems in the recent past. Salesman say those problems are in the past but have not seen a good amount of positive reviews lately confirming those problems have been resolved.

The range,from low to high, and the eveness of heat produced make the Thermador burners a superior choice. If you can really afford the $2200 I would get the Thermador. If it is putting a severe strain on your finances I would skip the Thermador.

grrrr......
if i see one more "clicking" reference, i'm gonna go postal.
i own not one, but two thermador rangetop/ag ranges. on rangetop circa 2003, yes, it does click on xtra-low. on 2012 pro grand, this feature/annoyance has been corrected. the ignitors on all settings are no more obtrusive than any other burner system.
i also wonder how often most would utilize this feature..sure, it's nice to have if you want to hold a beurre blanc for a while...
ok..rant over..we now return you to your regularly scheduled programming.

To me, this decision is all about the burners' shape - star vs circle. With ANY circle sealed burner, not just the KA, you get a cold spot in the middle; the heat is concentrated at the circumference of the pan/pot, rather than across the bottom. That's why true commercial restaurant ranges, like the Garland, have star burners. Of course the Thermador burners are sealed, not open, like a commercial range's would be. Nonetheless, the star shape is better.

One more thing - the KA is a dual fuel. Do you already have the electrical wiring for a DF range? If not, you need to include in your decision the cost of the electrician wiring for the DF. I prefer an all gas range - typically less complicated than a DF range which means less to break. Don't think that an electric oven is superior for baking - that's holdover thinking from decades ago when ovens didn't have electronic ignitors or much insulation.

Thank you so much for the feedback. I have to make a final decision by next Friday so it is very helpful. For the Thermador they will have to come in and recut my granite and indicated they could not promise that there will not be a lot of scratches on the edges. As a result I am leaning towards the Kitchen Aid and I actually have to add the gas line as I currently have an electric drop in Jen Air Range. I had really hoped for the Thermador because of the star burners but am now leaning the other way due to the granite.