I just think it's a cop-out, personally. Sorry, but I do.
It seems this is more about trying to compete with Apple, by making the X5 as 'slim&sexy' as possible, at the expense of actual performance-vs-battery life.
Well, slim&sexy does not make a flagship device.
Performance makes a flagship device, with all other factors being secondary to that. If I want to buy a device that needs a seperate amp to perform at flagship level, then I fail to see what the X5 brings to the table that isn't already available.
How do you know the X5 is supposed to be the flagship device? Maybe FiiO plans quite a line of devices. Maybe they're planning a juicier one down the road.
Besides, how do you know the market of power-hungry maniacs is all that big? I know I want to drive some orthos, but then you don't see me considering the E12. No, I'm looking at some balanced boutique DAC/amps. Maniacs are hard to please, you know.
Meanwhile, X5 makes total sense for those wanting better clarity and bigger storage than the X5 and rocking a reasonable choice of 'phones to use on the go. It also makes sense to some maniacs who might like its build, its features, its format support and kinda content with its price.