Sony Xperia XZ Premium vs Z5 Premium: should you upgrade?

So, the new 4K phone by Sony is out — the XZ Premium just hit, and it's as pretty as an exquisite marble... with tons of cutting-edge tech in it. You may be wondering whether it's good enough to entice you to upgrade from the 18-month-old Xperia Z5 Premium, and we will be examining this question here.

Design
The new XZ family of devices is supposed to be a re-imagined line of top-tier handsets, after Sony's Z series seemed to be going nowhere. But we wouldn't call the new design a radical departure from the Omnibalance form. Just like the Xperia Z5 Premium, the XZ Premium is a stark rectangle ...