WDD series faulty ignition.

I just want to share my disappointment with Mercedes Benz. It's the second time that I have to pay a fortune for a faulty ignition. There's clearly something wrong with their WDD series. This is my second car with the same problem. These cars are not reliable. You get stuck in the middle of nowhere without a warning. I'm really tired of paying a fortune to fix a fault that should be picked up my the manufacturers.