I believe Superman will win. He's faster, more skilled, and far stronger. Now if any of the team gets a good hit in then they have a high chance of winning.
So I'll say Superman fighting at his best can not only avoid their attacks but he can pummel them before they can react.
I would say Superman wins 8/10. The 2 losses due to an unlucky strike that stuns Superman. Superman at his best will have a low chance of this happening. This has been done before, maybe it should be merged.