Duncan.
He won a title with Robinson, Avery and Elliot.
Then without missing a beat.
He won titles with a completely different cast put around him.
He lead his team to 4 titles. (Horry was a role player on every team he was ever on in the NBA)
And yes, I harp on the leading teams to titles. That's what Russel did. That's what Bird did. That's what Magic did. That's what Jordon did. Lead their teams to multiple titles.
Looking at just stats, they are close.
Looking at their defense, they are close.
Looking at their leadership, they are close.
Looking at who stepped up and lead his team to titles, Duncan 4, KG 1.
And Duncan never had players as good as Pierce and Ray. (Robinson was past his prime when they played together. Still good defensively, but lost a step offensively. Much like KG this year)