Rudy's a better scorer, better defender. He's also at best Memphis 2nd option on offense behind ZBo, but they run a fair amount of offense through the Conley /Gasol tandem. Even before ZBos arrival, he was the second option behind Pau and when Mayo first arrived, Mayo played like he was the first option even though he was the inferior player.
The One thing you can say about Rudy is that he's always been comfortable in being a near 20ppg scorer with 6 boards a block and a steal regardless of whose on his team. He's just constant. Which I guess is comprable to Jeff, Jeff is who he is and very little can change that, his production is constant. It's just less profound than Gay's.