Should have said: Pre New52 Adam. I keep forgetting only Superman skirts the retcons.
On the fence about who wins. Both are pretty insane against peers. Adam can go full on "Psycho Crusher" and surround himself with magic lightning. Zod obviously has the heat vision (Which needs proof that it's stronger then Power Girls, who extended blasted Adam with everything she had and didn't slow him down.)
Suicide Squad was all done with a hole in his head.
Which he put there himself, by cutting out the kryptonite bomb in his brain.
It also interestingly proves a Kryptonians brain isn't as durable as their body, since Captain Boomerang made him cry out in pain (I guess they have pain receptors in their brain 🙂 )