I play off an 8 handicap and have been looking to move to the Titleist CB irons. I was going to purchase the 718 irons since the new 620 series just came out. The Titleist site indicates that the 718 series have tungsten in the heel and toe and are more forgiving than previous AP2 irons. The 620 CB has moved away from the tungsten and therefore i assumed that the 718 would be a little more forgiving and be a nice purchase at a discounted price. However the MPF of the 718 CB is 413 while the 620 CB is 465. The fact that the 620 MPF went up seems unexpected. Can anyone help me better understand?