A friend of mine is looking to get rid of his stock string and put in something a little better. He just start 2-3 months ago. I'd like to recommend a multifilament or synthetic gut, probably a syn gut, but I'm at a loss for what's good now. He has an eastern forehand that he arms, and likes to run around the backhand to protect it. When he hits the backhand, it's a weird 1 hand / 2 hand thing. He brushes the ball and is able to hit with a little bit of topspin. I'm aware that form and technique need to be worked on, but he doesn't like the stock strings at all. Any recommendations? xCel Power 17? NXT Tour 18? Pacific Premium Power X 16L? Pacific Power Twist 16L? L-Tec Premium Syn Gut 16?