I've only seen him against Wigan and Dortmund so I'm not going to pretend I know all about him, but he does look decent enough so far. He's obviously very fast and strong which means along with Smalling we have a good blend of physicality at centre back now. His positioning does seem a bit 'raw' but it could work in his favour, if Smalling just sits back then Bailly will be able to push forward and try to win the ball a bit more. There are still a lot of question marks but overall I'm very impressed so far. He looks a better player than Smalling was at his age.