I'm curious about thoughts on the nippon ns pro 850gh vs the 950gh in the AP2 714 head. They would be for my son, a 13/14 yo player who plays competitive tournament schedule. index is 1.5 and driver clubhead speed is 90mph. Currently he has the AP2 710 head with graphite aldila proto 75, but will probably move to steel with next change. I've noticed some of the better juniors in this age range with the 850gh shaft. 950 is slightly heavier, but looks like it may be higher launching. Just curious what some of the club fitters might think about pros/cons between the two shafts. Thx!