Crap, I guess my last post was cut. . .
He may be able to Janus; I wouldn't put it past him. But Mace could likely stand up to him, even if it came down to a Pod-Chucking contest. Not only is his saber style more effective, but he's markedly more aggressive than Yoda as well. Instead of dodging around, he'd probably throw a few of his own, although he can't match up to Sidious perfectly in that aspect.
Time to respond to this duel.
We've seen Mace take out Sidious on even ground - during the duel in Revenge of the Sith. I still am adamant in the sense that Mace is NOT the superior duelist. He did not outmaneuver Sidious with his blade. He won the fight, fair and square, but used a kick. This doesn't, I don't care WHAT you say, make him the better duelist. However, a kick is a kick, and a fight is a fight.
Mace is the superior fighter. He's more aggressive than both Sidious and Yoda, and looks to neutralize his opponent as soon as possible. But, we do know that Sidious did NOT use the Force until Mace knocked him on his ass. And judging from the struggle Mace had to keep Sidious's Force lightning at bay, I don't think he was a match for him in Force powers.
Sidious has the advantage here - in the Senate arena. He can chuck pods with ease. Movie evidence has displayed that he is immensely powerful with the Force - capable of lifting multiple pods in the air simultaneously.
If Sidious keeps his distance, uses his terrain, and uses his superior Force powers - he will beat Mace Windu. No question about it. But if he is overconfidant, and tries to take Windu out with a saber, there is a great chance he may lose.
And then you have Anakin and Obi-Wan. This is a far closer match than Sidious vs Mace. Anakin, to me, is undisciplined and inexperienced when compared to Obi-Wan, who is far more conditioned at battling Sith and using his opponents weaknesses against them. But, he possesses FAR much more endurance and raw power - which Obi-Wan simply can't compete with.
During the duel on Mustafar, you see that Obi-Wan and Anakin are equally matched. Obi-Wan's level-headedness, experience, and patience contrast wildly with Anakin's power, aggression, and strength. Yet both manage to keep up for each-other, blow for blow.
Obi-Wan moves to the higher ground. Ala Sidious, Anakin's arrogance got the better of him - not any real inferiority. Obi-Wan won the duel. But like with Mace, not out of any superior talent. Just superior patience.
On even ground, this would be hard. But Anakin may make the same mistake again. If he does, he's toast. If he's not, I say he wins in the end.