Edin Dzeko is a good goalscorer but he is rarely a scorer of great goals. He is excellent with his head in the box and has a habit of being in the right place at the right time. What he won't do is pick up the ball deep, skip past a player and smash it home, his game doesn't really consist of that.
He would be an excellent player to have if the men on the flanks are putting the ball in the box in the right area. Johnson has a great left foot and with some guidence could really become a cross specialist, on the other wing perhaps we could use an Ashley Young, another deadly crosser.
At 24 years old and 6'3, I'm sure he'll certainly fit the Mancini bill.