Use original MBZ pads! I recently saved $20 by installing Ate aftermaket pads and rotors on my '92 300D. Now the brakes make weird noises, like humming, and performance is less smooth than before. I shared my findings with my tech, who immediately asked if I'd used non-original pads.
You get what you pay for. I will shortly replace the front brakes with cryo-treated OE rotors and factory pads.
"If everything seems under control, you're simply not going fast enough" --Mario Andretti
1995 E500 street car
1986 Porsche 944 Turbo S track car