I voted Mace, While I also believe that the Emperor was letting Mace win, it was a similar way to Ben letting Vader win, and the Emperor trying to let Luke kill him. He knew he could not win, but in the situation, Anakin would swap to the darkside. There's no doubt in my mind that the Emperor would have died to create the most powerful Sith of all time. If Anakin hadn't of unchivalriously sucker attacked Windu, Windu would have been able to beat not only Palpatine but Anakin so in a one on one situation, I would give it to Mace.