Well my famous line is "The most interesting 1911's are all stamped with Super .38 Automatic"...And I stand by that. But the .45 ACP is just a wonderful cartridge in the 1911. So regardless of which you choose, I don't see how you're going to come out anything but a winner.
Something I will say is a plus for .38 Super. During ammo shortages, you tend to find .38 Super from time to time since it's a much less common cartridge.
