Ok, my friend uses either Monotec Zolo or Luxilon Xp, and he gets about 2 weeks out of each. He uses a POG mid, huge spin on his western forehand, pretty good off the backhand too. He used to use Kevlar, and get months out of it, but he said he just got tired of using it so he went back to polys. He doesn't like regular polys or Kirschbaum at all, only Luxilon. He broke Big Banger original really quickly, but loved the feel. He's gonna get ALU now he says, and will that be more durable for him? BTW, he strings at 60 lbs.