I really like the guy but his best position is previously that of Pogba's and now Bruno’s. Basically the most attacking and free of responsibility CM that makes his presence felt in the final 3rd a lot more. He makes surging runs and dribbles more successfully as opposed to Bruno's style of threading quick balls to the forwards. He's nonetheless still a risk taker.
I'm not opposed to signing him, but we still need a #6 dammit. Someone who can receive the ball from deep, be press resistant, be positionally aware and provide some shielding to the defence. We haven't had one since Matic went to shit 3 years ago before leaving. We have plenty of players who can play #8 (Eriksen, VDB, Fred, McTominay) or #10 (Bruno, Eriksen, VDB). Even if you argue SMS is a huge improvement on Fred, McTominay & VDB, which yeah he is, he's not a huge improvement on Bruno & Eriksen (imo) and thus he adds quality depth but not hugely improve the best XI. We still have no DM however.