My Stage 4 brake kit uses Mercedes rotors because they are the only off-the-shelf part deep enough to keep the fat calipers away from the spokes of a commonly available/reasonably priced wheel.

For some reason, Mercedes produces only ONE rotor with directional vanes. I talked to Centric about this last year at SEMA. They were getting complaints from customers about the straight vanes on their aftermarket rotors, so they recently started producing one directional rotor for both sides, just like the OEM Mercedes rotors.

Because Mercedes installs the same directional rotor on BOTH sides of the vehicle. I buy blank rotors and have them slotted (L and R), so at least they match the look of of the rear rotors.

Of course, Baer 2 piece Eradispeed rotors are also available, which almost double the cost of the brake kit.