I injured my shoulder (ac joint) which required surgery in Dec. I'm back playing now, but am concerned that racket I use may have contributed towards the injury. Unfortunately there's no way to know for sure if the racket played a role or not, but I want to play it safe. I'm a 4.0 baseliner using the npro open and play well with it. I know it's relatively light and does lack in stability. Recently I've been looking into other heavier rackets with more stability. I've demoed the pure drive roddick and the n6-1 95. I don't play as well with these rackets, but my arm is definately less sore afterwards (muscle soreness). With the pdr I can't seem to get enough racket head speed for short angle topspin shots. With the 6-1 95 I can't get enough on my backhand. Reading the specs of the new wilson cobra it looks good. Similar to npro open but more stability and a little heavier. I'm also going to try and lead up my npro opens a bit as well. Thoughts?