Damn these strings really DON'T MOVE. I have a habit of adjusting my strings after every point but damn, they don't even have grooves in them. There is just a slight kink and they are smooth. They play pretty well. I usually play with Syn gut @ 65 but these feel nice @ 60lb. My arms don't feel bad or anything. They have a really weird noise though. They really make a loud BANG noise when you hit. When I go for winners, it's like someone dropped a bomb on the court. I like them so far. How long before they lose playability usually? I'm using Big Banger ALU-Power 16L by the way.