The 767-400 is big ... still, it's no L-1011.
From my perspective in coach, long-haul is infinitely preferable on *any* 767 compared to *any* single-aisle.
Twin aisles just gave a sense of space and reduced-stress on transcon flights. And they're far more practical, of course, if you're trying to walk back or forward during food service (a beverage cart on a 737-800 is gonna block that aisle for a looooooong time).