Is he any good on Sensible Soccer?
On a serious note this kind of signing along with signing players ready for the first team is important for our club. We'll win some (Coleman, Stones) and lose some (Gueye, Vellios), but not every superstar moves for mega money on their first transfer, while some that do (Bebe) can fail miserably.
It's as much to do with the players attitude, how they are used by the club and what guidance they receive from the manager. I think a young attacker like this lad can flourish under Martinez. He seems highly rated if United are amongst the clubs tracking him, and maybe we've just stolen a march to get in there early.