I have been a 11/12 index for years. During that time, I have been playing the Pro V1 most of the time. My wife bought me a box of AVX for Father's Day and my last 4 scores have been 77, 77, 78 & 79. My index is now 9.5 and trending to 8.9. Although I did switch back to my old irons last month, I am afraid to change the ball since I think the AVX has been the biggest impact. I was concerned with the lower trajectory since I tend to have a lower flight on my driver, , but my drives are long and straight (even of mishits). Around the greens the ball stops on a dime and I can spin it. My putter has been great as well. I think I am a believer!