We replaced a Jenn-Air wall oven/microwave combination unit after it failed with a similar unit from Bosch. It failed after just a month. Bosch were utterly disorganized and disinterested in fixing the problem. Three months later and multiple long phone calls with half-trained monkeys in a customer service telephone pen, two circuit boards and a new microwave unit were replaced. Then a month after it was all fixed and working per specifications,, we get calls from Bosch telling us that new circuit boards are available for pick up and installation.
I'd never specify Bosch again for any of our projects. Highly suspect design and manufacturing and the worst customer support we've experienced in a very long time.
Thermador every time! The build quality just feels better and if they are selling the apartments, Thermdaor is a good selling point.
Both are good and probably have similar insides. It really comes down to the style you are trying to achieve.