I can think of some advantages of the BB Chevy, including you can buy one new with modern EFI if your pockets are deep enough.
Another is related, in that even the first generation BB's are more common than the Cadillac, and both performance and standard replacement parts are easier to buy at your corner parts store.
I have a Cadillac 500/Turbo 400 combination sitting in my shop with every intention of installing it one of my old trucks someday. I also have a Chevy 454 and may put it in the project truck sitting in my shop right now.
They both have a place and neither of them will go in one of these trucks without some modifications.
