Originally Posted by born sleepy

As someone who has extreme difficulty sleeping on planes, even in lie-flat J, even after an Ativan or two, I would prefer the daytime flight. I'd be awake for most of it — I can nap a little but no useful REM sleep — then crash at the airport hotel and get the first flight out to ATH the next day. I've been to London plenty and wouldn't waste the time/money to go in for half a day.