Depending on the vehicle, either a one- or two-piece rotor is used. The one-piece rotors come 'e-coated' to protect against corrosion. The two-piece kits feature an iron rotor mated to a CNC machined aluminum hat to reduce unsprung mass. Ceramic pads keep dust and noise to a minimum while providing excellent stopping power in all conditions. A more aggressive pad is available for track applications. The braided stainless steel lines (included) work to improve pedal feel and clamping force. All Rotora kits are direct bolt-ons, requiring only minimal modification, although some kits will require larger than factory wheels.
A well-engineered big brake system is largely transparent-it should feel and behave like the factory brakes with a slightly firmer pedal. There should be no grabbiness or non-linear pedal modulation. And after hard use, big brakes should remain functional after the factory binders have given up.
Essentially, that's an accurate description of what Rotora big brakes have done to our 645i. They feel exactly like the factory brakes only better. And we haven't even mentioned the look of them. The blue anodized calipers (visible between the black spokes) look awesome.