Malgus can't do what Mace did, because Vaapad hasn't been invented yet. Mace only lasted as long as he did because of that, any other form he would have gotten killed quickly and really Mace only won because he exploited a fear which was coming from Anakin who was on the way. Prior to that point, Mace and Sidious were fighting at a stalemate, even then Sidious could have ended the fight at any time with his Force superiority, Mace only lived so long so that Sidious could turn Anakin.
Sidious is more powerful then Malgus in every aspect, saber combat, force power, etc so there really is no argument your right.
No the fight wouldn't go either way, because Mace would mop the floor with Malgus using Vaapad.
Now this thread really needs to stop, it should have stopped after the 1st post. There is no way, Malgus is beating Sidious...at all.
I disagree, I understand that form is very important but I donít think that it is an auto win over experience. Malgus is a master duelist in a time when Jedi vs. Sith fights are common. Mace and Sidious are masters of form in a time when Jedi vs. Sith fights are uncommon. So I think that Malgusís experience gives him an advantage that you not taking into account (at least against Mace). Now I know that Vaapad is a powerful form, but is it really so powerful that no other form can beat it?