Thread fail. U_U
Regardless of whether Itachi's Susano is stronger than Sasuke's even with the spiritual weapons, Itachi still takes this by using Izanami.

Although Itachi would lose an eye in the process, but the outcome would be Sasuke looking idol while his mind is running in circles.

Another thing is that Sasuke doesn't know how to break out of Izanami, whereas more skillful Uchiha such as Madara and perhaps Obito can probably get out of it more easily. :yeah:
Pff... the same can be said about Itachi. :| He has Shisui's blessings. :yeah:
SHISUI gave him MS
SHISUI taught him about the "will of fire" ideal
SHISUI taught him how to live like a loyal and skillful ninja
SHISUI taught him everything he needed to know about genjutsu
If it wasn't for Shisui, Itachi would be a good for nothing weakling not worthy of being considered an Uchiha and thus he would probably be eventually killed in war or a battle. U_U