Supposedly quieter (which they are), and truthfully, the vacuum actuators are pretty reliable (I could get flamed for this).

When age takes a toll on the hoses, that's when trouble erupts.

MB has since changed that viewpoint, since my ML has electric ones...

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car