I have been in the sport for over a year but was not very regular in the first 9 mos due to work schedule. Aug last year, I bought an ISO SP SX, suited me very well since I smash given the opportunity. Gave me difficulty controlling at 22lbs though. But I was happy with it. Forgot my racquet once and I picked up a friend's old Prince (heavier, a friend said its not a "professional racquet" bec of the joint - later bought it for $12USD). I was playing better! Better drops, more powerful smash. I occasionally experience pain with my ISO (from straining and poor technique???) . I also get a painful sensation when what I could only imagine as shoulder muscle would "cross" from the top to the front side (sorry for lack of technical description). I had to pull something heavy or fixed to get it back and the pain is gone. This rarely happens with my use of the Prince racquet. I am classified as a beginner in our village tournament. What would you say: 1. Is the Yonex racquet giving me pain because it is lighter? 2. Should I discipline myself and drop the prince racquet so I get use to my ISO? 3. Is there a racquet that will suit me better? Sorry to burden you with this.