All the stuuf you listed BlackMercedes I have never had any problems with that caused me to think of poor quality.

Constant head gasket problems -
One head gasket in 245,000 miles because the car had been overheated badly once before

Never-works cruise control
Never had any problems just like new

Breaking ACC units
Just a little leak nothing else

Failure prone evaporators
no problem

Driveline vibrations
none
Power window failures
one in 16 years

Poorly made valve guides
no problems

OVP relay failures
no problems

Hydraulic door-closer failures
none

Blower motors buried deep - real deep
no problems

Poorly made wiring harnesses
it's german of course problems here