There is nothing necessarily wrong with ceramic pads other than they tend to cost more and their initial bite is not as strong as I like it to be. I used ceramics on trucks primary used for towing and found out that they beat up the rotors very quickly. Another difference I experienced is the initial brake bite on the pad, specially when cold is better on semi metallic pads. I have a 5000lbs Suburban that I use to tow a 5000 lbs travel trailer. My braking performance has been vastly superior with semi metallic pads. Most people buy ceramic pads because the dust is lighter in color and not nearly as sticky as semi metallic pad dust. I usually wash my wheels on weekends so the dark brake dust generated by the semi metallic pads is a non issue for me. One big complaint about semi metallic pads is brake noise, ceramic pads vibrate (make noise) too when braking but vibrate at a frequency that is higher than human hearing. I found that properly bedding the pads when 1st installed is key with noise. All 3 of my vehicles have semi metallic compounds on them and we experience no brake noise. There is lots of contradictory advise on the web. I do also know that semi metallic pads pull some of the heat away from the rotor during high temp braking whereas ceramics do not draw as much heat out. If you are selling the car, it almost should not matter, any pad will stop the car. The question is how effectively. I just bought a 2004 3 series and the first thing I did was replace pads and rotors, mostly because they did not have that BMW brake "feel". This was more pronounced when brakes where cold. Hope this helps and wish this does not turn into a ceramic vs. semi metallic thread (already too many of those). Everyone has an opinion and a different set of evaluating criteria. I just provided you with mine. Good luck.
Currently in my Garage
2010 A3 TDI
2000 Suburban LT 4X4
2012 Jayco Featherlight trailer
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