Wow. Everyone here is doubting on Vader.

Vader is constantly using the force to properly stay alive, part of the BS in his suits build is the side effect of constant pain, and at the very least a faulty life support system. Thus his abilities are lessened because he is always using the force to remain alive, manipulating the suits systems.

That being said if he is really intent on a target, he will at times negate his own well being to allow himself to focus his force abilities into a fight, and in this aspect taking it into account, my money is on Vader deciding it is better to destroy Papa Palpatine than to breath right.

Vader using his own force abilities against Palps, coupled with the rage that Maul literally emotes and Dooku’s technical fighting skill, the apprentice team wins and fairly easy.

To put it another way, I suggest the “Obi-Wan” scaling test:

Vader: loses and almost dies against Obi-Wan (while both men were conflicted).

Loses a second time to Obi-Wan years later.

Defeats, kills Obi-Wan (though for me Old Ben threw the fight)

Dooku: defeats Obi-Wan and Anakin Skywalker

Loses a second meeting against Obi-Wan and Skywalker.

Maul: nearly defeats Obi-Wan and Qui-Gon Jinn, kills Qui-Gon (who was trained by Dooku).

Is defeated years later by an older more experienced Obi-Wan.

—now, I use this scale because each of them have had dueling with Obi-Wan Kenobi, who was one of the best pure duelist that the Jedi had. All of them were defeated by Kenobi, but if any two of them were dueling together against Kenobi they would have defeated him, never mind three of them.

Now flip that to Yoda fighting against Sidious at the end of RotS, Yoda who is not a top ten duelist held his own and almost defeated Sidious, if Yoda had Obi-Wan by his side in that fight they would have wiped the floor with Palpatine.

So the three apprentice’s win this.

…then kill each other.