Heated or cooled seats. Ultra-high-definition TV screens. Benches. Convertible beds. All-aisle access. And of course, the coveted privacy door. Ever-more luxurious first- and business-class cabins ...

JAPAN Airlines is the first airline in the world to introduce cabin seats with built-in speakers - and I tried them out. Japan's public transport is famously silent, a far-cry from UK trains and ...