How many miles do you have on your present rotors? Chances are fairly good that your problem is deposits of brake pad material on the rotors, which can be removed.
I have been looking into the same replacement issue myself, at least for the front (pads about gone; rotors will have to be turned for new pads; and not enough thickness would be left in the rotor after turning to be safe). At the present time, I am leaning toward (not yet committed to) DBA "standard" rotors
from a site sponsor and Hawk Performance Ceramic pads. The questions remaining in my mind are whether the DBA rotors are sufficiently better than the stock rotors from
another site sponsor to justify the price differential (just about double: $60 per rotor, plus shipping
vs. $229 per pair of rotors, shipping included), and whether Raybestos (a trusted brand name) rotors (less expensive than Mazda-sourced rotors) are just as good as Mazda-sourced rotors.
As to pads, everybody in warm climates has good things to say about
Carbotech Bobcats, but I have heard some questions raised whether they warm up quickly enough to drive safely in 40-50 degree (F.) weather and lower temperatures.
There is a very informative post by a fellow named Rob Levinson in a BMW forum
here. (
I found it helpful, at least.)
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