I must be on a different page than everyone else. I have flown both carriers in coach. I would take CI over OZ in a pin drop.
I have had awful experiences with both of the Korean based carriers. I have only flown OZ once but many times on KE.
My CI flights were nothing to brag about but definitely better than OZ. But that is just my opinion most of the FTers here seem to prefer OZ. You did ask about business and I have only flown coach.