Of course itachi > obito.

[YellowFlash1]

Agreed itachi is better then tobi..even tobi knew this thts why he waited for itachi to die b4 he planned the attack on the leaf

I think the real question is why did itachi kill tobi when he was alive ?

He knew he couldn't kill Tobi which is why he waited till he was dead and tried to finish him ... It didn't work which means itachi didn't really know much about Tobi.

If itachi tried that when he was alive, tobi would off killed him! The reason that tobi never wanted to kill itachi was the fact he was a great asset to the akatsuki ... So there was no reason to kill itachi as long as he did what he was told, which is what he did ....

Tobi > Itachi