I ADORE them too as Horowitz's records. But the most important reference is, as jdskee wrote, the Scott Ross's records. I didn't heard all of them by him, but I was deeply impressed by those I listened to. I heard he made that record very close to his death, they were as his legacy. If someone could extend himself about this, would be really interesting to read.In Deutsche Grammophon there is another version in piano by Alexis Weissenberg, I love this record too.