Old vs. new, or: a surprising conclusion from travelling to Japan
I flew to Japan on an Airbus A350 (departing Munich) and left Osaka on a Boeing. Even though I wasn't travelling in the same class, the comparison struck me as very interesting.
A350 — I was sitting at the boundary between Premium Economy and Economy, in the first row of Economy. That seat was incredible. I could crouch there, turn around... The Airbus is quite spacious and doesn't feel as massive.
B747 v1 — The Boeing gives a more imposing impression. My seat wasn't at the start of the section, so the legroom can't be compared to the Airbus (there was far less). Even so, compared to an Economy seat on the B747, Premium is much more comfortable, not to mention the larger IFE screens.
To sum it up: if you're flying Economy you can find seats that passengers in higher classes might envy — at least in terms of personal space. And you'll save money on top of that!