Depends...for doubles, the BS09, for singles, the BS10. BS10 is head heavier and stiffer, which is nice for singles as you've got more time for each shot and accuracy is more important than speed. The BS09 is not as head heavy as the BS10 - I felt that way for some time too, but it's really not. Sometimes a slightly softer shaft can make the racket feel a little head heavier than it is as the racket head does not follow your movements as sharply as a stiffer racket would. One of the reasons the MX80 feels so very quick, imop. Anyhow, I rarely use anything other than those 2 and the PP Trinity 2.