I'm using a Wilson kTour and had been using a hybrid of Hurricane Tour (mains) / VS Natural Gut (crosses) previously. This summer I switched to Babolat RPM (17) in the mains and kept the VS in the crosses. I loved it. I added a lot of power. I hit pretty flat (tiny bit of spin) but my shots stayed in and penetrated well. Unfortunately, my elbow and shoulder are starting to kill me, especially after 4 or more sets during practice. If I take a few days off, it heals up OK but I don't think the RPM is going to work out because I like to play ~ 5 days per week. Anything softer but comparable to the RPM in terms of power / keeping the ball in play? If I put the RPM's in the crosses and VS in the mains would that be a more arm friendly alternative? I'm also open to using all natural gut. Just need my arm friendly power! I rarely break strings.