Let's see what we got here regarding them as Jedi:
Dooku > Mace:
- "Master Windu himself remained perfectly balanced and centered. In the history of the Jedi Order, only two opponents ever overcame him in battle. One was Master Yoda, who some said was the Order's true master of lightsaber combat. The other was former Master Dooku, whose own fighting style was archaic, yet stunningly effective." - Power of the Jedi Sourcebook
- "Dooku had been reckoned one of the foremost duellists in the Jedi Order, second only to Master Yoda." - The Official Star Wars Fact File #60
Dooku = Mace:
- "Before leaving the Jedi Order, he was known as one of its greatest duelists, a match even for Mace Windu." - The Clone Wars: Heroes and Villains
- "He assisted in Dooku's combat training and as a result, the Padawan became especially proficient with a lightsaber. Only Masters Yoda and Mace Windu were considered to be on equal terms with him." - Insider #109
- "Only Mace himself ever mastered it, and it was reckoned that only Master Yoda and Dooku were ever able to match Windu with a lightsaber." - The Official Starships & Vehicles Collection #25
Mace > Dooku:
- "Under Yoda's tutelage, Dooku became one of the greatest sword masters the Order had ever produced - eclipsed only by Mace Windu and Yoda himself." - The Official Starships & Vehicles Collection #48
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I'm inclined to put them as rough equals as Jedi with Dooku ever so slightly superior due to a minor Force edge.