Fan Casting Shazam vs Superman

Both Superman and Shazam have a similar lineup of powers. They're both incredibly strong, invulnerable, and have the ability to fly at great speeds. And where Superman has heat vision, cold breath, and other useful powers, Shazam can call down lightning and even bestow part of his power to other heroes. Superman and Shazam have had some epic battles over the years – but which one of these god-like beings would really win in a fight?