On merit of his recent upgrades of both body and mind, I'm willing to give Surfer 4/10 against Darkseid. That would be better odds than I'd give Superman at taking Darkseid (2/10). Darkseid will have to do better at putting down Supes before I give 'Seid a more decisive win.
That, and Surfer is simply a beast now. I can't wait to see if he and Thanos get into a tussel.