Your comments make me recall another obvious factor: It is not only the pads, but the strength of the hydraulics behind them.
Your C280 braking system is, I assume, stronger than that in my 260E. A hard pad in a strong braking system would probably behave in the disappointing manner you describe because the pedal pressure you apply in your car puts greater relative force on your pads than the same pedal pressure would do in my car.
The strongest brakes I have experienced where in a 98 S500, with OEM pads. A light pedal touch would stop the car on a dime (almost). Metal Masters in that car would be excessive, and would probably warp and damage the rotors quickly, as you described. Because your Mintex pads are softer than the semi metallics such as Metal Masters, their behavior is thus within more acceptable operating parameters.
2001 E430 4matic
Gone but not Forgotten:
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black