You get a rare from Sage about every 60 pulls, and since there is 3 rares you have a 1 in 3 chance of pulling Naruto.

Now I would say to wait to pull until there is a selective rebate. And then let that decide for you! If Kage is in there then pull Kage, if Sage is in there then pull Sage!

But as to which is better, I would say Kage is better.