Change from BMW to Mercedes – meaningful?

After my third BMW has a brand new 523i only defects and I am really operated by the BWM service I will change it with all prudence which should legally not be a problem since it already has the fifth high-pressure pump and the third injector defect within eight weeks. The C-Class is too small for me and the existing E-Class unfortunately did not convince me from driving. Therefore I speculate to get an S-Class as an annual car or demonstrator. My questions to the Mitgli 1) What is the reliability of the new S-Class? I drive almost only abroad and defects at night in the province of France like this week with my BMW are really annoying. 2) What is your experience with the Mercedes Service in the event of a breakdown? At BMW I have received mostly one or two classes worse cars so far, which is simply unreasonable with the frequency of repairs and the telephone service was extremely mixed from outrageous to very hard. 3) Where are the actual consumptions for the smallest gasoline and the smallest diesel according to your experience. Thank you in advance