I'm F2P player. Currently Level 94 with only 89k battle points. I have 11k Coupons.

Is it worth it for me to get Killer bee? Or is it better for me to keep on saving? Because i'm not sure on how do i use my coupons efficiently. I have Kushina and normal Roshi

Plus I always use my coupons on things like lucky board and stuff like that. Making my coupons to remain at 11k for a long time.