if your doing the 850 upgrade then I think your completely wasting yout time and dreams on nothing! will probably stop better without the holes and the theory behind the hols is when the rotor gets RED hot it helps dissipate some of the heat a little quicker. With the 850 option I can pretty much bet your not going to even be able to get them red unless your stopping on a steep hill with a motorhome attached to your trailor hitch.
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy