A 600 mah. 4 cell nicd battery is more than good enough. It will give a minimum of four to five flights with the TS69 servos. I run a 61FX with a 600 nicd pack with HS422 servos. I never had to add any weight for balancing. And get a minimum of four or five flights before recharging.

Of course there will always be a recommendation for a 2400mah pack. But honestly on a Four Star 60 it is not needed. Heck even a 1200mah pack would probably go fifteen flights before it needed to be recharged i am sure you could get seven flights out of a 600mah pack.