Builders: Square engine, Over Square, or Under Square for you?

The small block mopars have some of the best rod ratio compared to the other brands. Must be a place a builder would love it to be.
Best "for what"? I think that's splittin hairs. Short rods are good if you want piston speed up. Long rods are good if you want piston speed down. It all depends on what you're doin.