With all due respect, that's bollocks mate. I am not sure I'd replace Laporte with him as they are pretty close, but he is miles better than anything else we have. And I'm fairly sure you'd be over the moon if he signed for City tomorrow :D Him and Laporte at the back, wow
Although he doesn't play for a rival Koublialy would be my choice. Both are the same age and Koulibaly doesn't seem to have an ego.