Who do you have?

I guess we have to start off by setting a timeline so we'll say the moment of palpatines attempted arrest each at full strength and 1v1 no inference.

Personally I think given the experience, wisdom, strength and skill of Mace that he'd be the winner. I concede that a later Darth Vader would definitely take the win but am quite certain that had Anakin remained a jedi he would take much longer to acquire his true power.