I've been wondering this for a good while, and i'm leaning towards Head Light. I don't think anyone could add a substantial amount of lead to the head and still get as much racquet head speed as the pros do. I understand that they are stronger, but I don't think anyone is strong enough to use a 12+ oz racquet that is head weighted and still whip it like they do and have as much maneuverability at the net. Does anyone know for sure? I think they may add weight to the head and then custom handles? It makes alot more sense for them to have a head light racquet because it is better suited to racquet acceleration, no?