I take this flight quite often and that too on a revenue ticket. However, these are work trips so different to-do’s than if it were vacation.

For me, the key is to eat before boarding and then get on and stay awake for the first 2-3 hours. Then I sleep right up to landing. Close to 10 hours of sleep allows me to schlep my way through the entire day before an early’ish night.

FWIW, I would choose a lie flat product over an upright one every single time for a flight time of approx. 14 hours.