Found out that most Japanese made drivers (Yonnex, Royal Collection,...) have a swing weight very low compare to US made, usually D2 to D2.5 while US made is D4 and even D9 for taylormade 2.0 Burner. Any particular reasons or advantages? Body built, height?
I try the New Yonnex 450 driver 9 degree with NP 50 stiff shaft and it feels light and more control.