Hi, I'm looking for new racket. My style play is love to smash some cut and drop. (playing double most) My old racket is Armortec 800 Offensive (4U), but after playing I always pain at my shoulder. and now my choice is Lining n9 or VT Z Force II I would like to ask that 1.which one fit more for me? 2.which one is faster racket? Thank you.