I enjoyed The Hangover more. Jonah Hill is funny as fuck in Superbad but the whole McLovin/Seth Rogen subplot was lame as Shit unless you're 15 years old.
If you're under 25, you probably prefer Superbad. If you're over 30, and understand the need to escape married life, you probably prefer Hangover.
Plus, most people probably missed the polaroids sequence at the end of The hangover, which was hilarious.