I don't see it
I must strongly disagree with those who assert that CX has a better seat in F than BA does. BA's seat is preferable in every way, IMO. Not only can you have a guest join you for dinner with the 'second' seat, it's also makes a more comfortable bed, not to mention the extra privacy the layout of the BA cabin gives you.
Service is definitely amazing on CX, but I would still give BA the edge.