Wouldn't have to be "concours" to be desirable to everyone. I am TOTALLY stoked my ERA has a 427 S.O.
I would have been happy with a 427 C.O., or even a 428, a 460 would have left me "bummed".
I think it is SO cool to be able to say, "I got a 427 S.O." End of story, no elaboration about how some of them came with a 428 or the 460 is better or whatever.
,,,,man I'm gonna cry when I blow that puppy up on a missed gear shift.
You KNOW I'll replace it with a "modern" block, and it won't be the same.