R1 Concepts are China rotors which they stamp their name on, started selling on eBay like many other rotor vendors. Same as anything you buy off IMC parts under their brand or OP Parts. Save a little more and just buy OP Parts brand from China it's the exact same thing just without the eBay name attached to it.
Have had r1 e-line rotors for a little over two year. No warping but never had the stock warp on me either. Noticed my front rotors are no longer smooth though. Feels like little condom ribs on the surface.
So this coupon is awesome since i doubt i can find a place to resurface the cross drilled and slotted rotors.