So the premium is merely for a BIOS with built-in overclock settings? Do they do any kind of testing at the factory to ensure that it holds the overclock well or are you really just paying for a different BIOS that you can flash yourself?
For the SC, yeah that's pretty much it. I'm sure they've tested enough cards to know their SC is going to be something they don't need to cherry pick for.
When you get to the FTW and above, you're paying for the extra BIOS, custom PCB that's a lot more robust, which MIGHT allow for a great overclock.