Raybestos 980283 High Performance Disc Brake Rotor - Premium Auto Brake Rotors for Cars, Trucks & SUVs | Advanced Smooth Braking Technology | Durable & Reliable for Daily Commute, Highway Driving, Off-Road Adventures | Perfect for City Traffic, Long Trips & Rough Terrain

I bought these to replace cheapos from the *Zone that had developed severe brake shudder and a continuous shimmy in the steering after just two years. I did not measure the Raybestos rotors, since I don't have a dial gauge, but they completely eliminated the noise and vibration with a new set of Professional grade pads, so they must be pretty straight. The vent channel runs perfectly parallel to the disc surface.The black paint on these is important to keep the disc from rusting solid to the hub and to give a clean, flat surface for the wheel. Otherwise, as I discovered, you have to wire brush the crud off the mating surface when you change wheels and then coat the surfaces with antiseize to keep the wheels from getting stuck. (Plus the discs themselves rust solid to the hub flange and, in my case, even a 4 pound sledge and liberal use of PB Blaster wouldn't break them loose.) The OEM rears were coated and have stayed clean through multiple winters, so I expect similar performance from these.These are the same as Napa "Super Premium." It's a shame you have to buy names like "Super Premium" or "Advanced Technology" for it not to suck, but that's the state of affairs these days.I'll change this review if these discs fail to meet my expectations.