Start – Stop Automatic

Hello all, I’ve done a test drive with a new Mazda 6 (2.2l diesel, 150 hp) and a Mercedes (C 250 CDI, 204 hp, BJ 12/2012) in the last few days. I noticed that the Mazda was quieter when starting (in the course of the start-stop automatic) than the Mercedes. The Mazda dealer explained to us that the engine runs out in a certain position so as to “better” start again. With the Mercedes it sounded like when starting. Is the technology of Mazda the better or more How do the other manufacturers (BMW or Andi e.g.) make them? Are there advantages and disadvantages to the different systems? Greeting, Andi