I can't imagine that these rising juniors start using prostock racquets when they're 12yo. They probably use off the shelf retail racquets no? I see most high level juniors around here use frames like the GrapheneXT Radical, Pure Drive, Pure Aero. At what point do they get sponsors to provide them customized prostock racquets? Maybe things are different now than they were back in the 90s when the current pros were juniors.