CEntrance HiFi M8 output, battery level preference?

http://centrance.com/products/new/blog/2012/10/03/output-level-dilemma/ More output power, or more battery life? In short, do you need to drive tough-to-drive headphones? Are you willing to sacrifice battery life for it?
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DacPort power output DacMini power output

4 hrs 10 hrs

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