I'm currently playtesting the Fischer M Pro Number One 98 Light, the Boris Becker 11 Light, and the Wilson K-Surge. I had about determined that the Fischer was my favorite of the bunch but I had a chance to play 4 sets of highly competitive doubles yesterday and the Wilson K-Surge really stood out. Very solid at net, lightning quick up there also, excellent topspin and slice, fantastic on serves (quick racquet head speed and tremendous kick), and reasonably solid from the baseline considering it's weight*. This morning I woke up with some soreness (not really pain) in my shoulders, especially in my serving arm (I serve lefty and play righty). I'm not sure if it was due to the stiffness of the K-Surge or the fact that I played four sets without a break, or because I used four different racquets (3 mentioned above and RDS002 Light) during that time frame. Has anyone here experienced arm problems with the K-Surge? Any other racquets you can think of that have similar playing characteristics but a little more flexible? Thanks. TripleB * I was quite shocked that I liked this racquet: it's head heavy (which I've never used before), it's only 10.3 ounces, and it's on the stiff side.