The discs will be really good discs now.
Rust is good for them.
A lot of people pull a funny face when they find out the difference between a Brembo racing disc and a standard disc.
the Brembo one is left outside for 18 months and allowed to go rusty then machined back to a shine and sold.
the rust relieves the stress in the metal so they are less likely to warp
this is a steal price tho, wish i had the money