Try re bedding them. It's helps a a lot with these pads. Mine were toast after two years on my old 330ci. I too had a lot of metallic noise with those pads and zimmerman rotors. I recall actually like those cheaper akembono pads over the HP.
"I catch you in my dreams, just me and you. But you seem confused, I'm not trying to break the rules.
So why do you feel the way that you do? So why do you feel the way that you do?"
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