Ok, i play Babolat Pure Control Standards. I usually play them stock w/ an overgrip and strung with a high-end multi. I just p/u'd a PC strung with Pro Supex Big Ace@ 58lbs, Wilson Leather and an overgrip. I like this set up. It's more HL than stock (heavier grip) and the Big Ace feels great. Again, i like this set up. So i decided to experiment. I took off the leather grip (the stick with the Big Ace), put on a Bab Syntec and overgripped it. It felt like my stock PCs. But after i changed the grips and went out to play, my arm started to hurt - elbow and shoulder! I never had a problem with my old set up, which this is now similar. Could the poly string with a syn grip, (a now more head-heavy racquet) have a big effect to pain my arm? Does the heavier leather grip give the racquet more stability? Vibration control? Chnages the balance to compansate for a stiffer string? I put the leather back on and when my arm is feeling better, i will re-hit and see how it feels.