They arrived. They look identical to the BMW Performance rotors. For reference, Pronto is PBR's rotor brand. PBR makes Axxis/Metal Master/etc. brake pads and is pretty well known to be a decent brand. And for $100 vs $350-400 for the BMW Performance rotors, this is an incredible bargain.
They make the fronts too but I already have BMW P fronts. Anyone want to check out a set? They are apparently exactly the same with the aluminum hat and low weight too.