i have one iso 900 before,and i felt it is even head heavy than ti 10 2U,and some say its head is not so heavy, and many like this racket, but i am one who like light rackets such as TiSP SA and i use most arm power,i dun rely on the heavy heaviness of a racket to generate a powerful swing,,and a question to anyone who has both rackets,which one has a heavier head?