I'd go with Tim for the reasons you mentionned on OP tbh This game was especially big because he throughly out-played Shaq and broke the 3-peat despite some thunderous comebacks by LA.
TP against Memphis was in beast mode, during this kind of game you feel he truly dominates the game and does what the he wants. Few PGs in the league can do that tbh CP3 has this kind of games too but Duncan 03 performance was epic and against one the most dominant big of his generation. So this one goes to Tim