I highly recommend the book Darth Maul : Shadow Hunter. What he does in that book makes Jango look like a noob.
So yeah, Maul would probably win.
That being said, I do think that Boba (in his prime) is better than Jango. At least he's more famous. And I'm pretty sure that some of the EU stuff has it that Boba has killed a bunch of Jedi during the purge. If we take that for the truth, then I think Boba would stand a chance against Maul. Let's not forget that Maul was owned by Kenobi when he was a mere padawan...
...but then, Boba was owned when a blind guy poked his jetpack...
~Dark Cupcake of the Sith