Well its all a balancing act. With a bigger battery you will have more mah's but you will have to fly with higher throttle because its heavier, with a lighter battery you have less mah's but you don't have to apply as much power because its lighter. This one I would say is about five to eight mins flight time (depending on how you are flying) Another thing to take into consideration is that a heavier plane is going to be harder to fly. (Heavier not bigger

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