"The battery survives well in standby mode, because of the handset’s power-saving facilities, with the display on juice drains quickly. We only got a tad over four hours when media streaming – insignificant when compared to the six hours from the HTC One X+."
This is even a worse look into battery performance! It would just mean that you need to plug this to charge whenever you can if you heavily use the XZ. Sony really needs to do better to increase WHILE the screen is on and not just when it's off.
Tell us honestly, actual users of this device: How much SCREEN-ON time do you actually get from a full charge? The above report says just over 4 hours. It's it the same?
SG Note II rooted with stock 4.1.1
Even if a breakthrough technology was announced tomorrow, it would take years to be realised in a commercial setting. Realistically, if you want high usage out of a high-end phone then you'll have to make provision to charge it away from home - ie. a spare charger/dock that you can keep at work, an external battery pack that you can pop in your bag, a spare battery if you have the removable option. It's obviously not an ideal situation, but all phone manufacturers are restricted by the slow progress in battery technology improvement.