Thankfully a choice I will never have to make, having been smart enough my whole career to run integrated amps. But if I ever did go separates I would like to think I'd be smart enough to know the best cable goes between the pre and power. That way every source always goes through your best IC. The idea of once its lost upstream is a red herring. At least I think that's what its called. Do herring even swim upstream? Nevermind. The herring is a MacGuffin anyway.