My 12 year old daughter switched from her 2 year old 30 inch 20 oz rockettech to this years CF5 31 inch 21 oz by Demarini . The CF5 is definitely more balanced which brought her bat speed up even though the new bats heavier. She went from periodically 1 hopping the 200 ft left field fence to hitting the fence at least once every bucket. By the spray pattern of the balls id say she gained 10 to 20 feet per hard hit ball. Her grounders are hot! Infielders beware. Its upped her confidence and increased her bat speed.