Hello. I would like an opinion on which string would be better for my son. He hits with the Head Youtek Extreme MP and he has play tested two strings so far, Head Sonic Pro 17g and Genesis Black Magic 17g. He likes both strings but he gets different responses from them. The Sonic Pro gives him good depth and topspin, the type of spin that jumps high off the gound and pushes his opponents behind the baseline unless they can step in and take the ball early or stay at the baseline and hit the ball above their shoulders. The ball feels good on his strings. He likes the spin and jump he gets on hs serve. The power is OK. Slices sometimes tend to go long. Tension at 40 lbs. The Black Magic gives him good depth and spin. This spin allows him to hit as hard as he can and the ball stays in. He does not get the jump off the ground that he gets with the Sonic Pro. So the ball bounces into the strike zone of his opponents. He gets great power however with the Black Magic. I've never seen him strike the ball so powerfully before. His volleys are crisper with the Genesis and his slices land just inside the baseline. The feel is good but not as good as the Sonic Pro. Tension at 35lbs. He is only 12 so of course we will probably be changing strings a hundred times in his playing career. But for now, which string sounds it is better based on the playability that he gets. Thanks.