I fondly remember Andrei Frusumanu's article on anandtech tech ,when he reviewed the Galaxy Note 3 neo and said left to him a hexa-core SoC was the most logical chip core count he would have preferred, as they strike a balance between performance and efficiency,I vividly remember.

Thus I likewise use a Smartphone with a six core SoC ,and believe me battery life is good,and even it's successor is finding it challenging to dethroned it in terms of battery stamina.