If I rule out rotors,pads,hydraulic lines,no loss of fluid,no vacuum leaks.

And my 2000 Ml320 exhibits symptom#1 can anyone argue the problem might be elsewhere or some other combination.

Symptom#1 Pedal requires a lot of leg, to stop. (points to master cylinder)

Symptom#2 Pedal very hard to push, to stop. (points to booster)