Hmm. I will look into that for you as soon as I find 'the books'
I know Canada3000 Airlines does Vancouver-Calgary-Keflavic-Amsterdam with the same set up as a Vancouver-Toronto. Keep in mind this is in cattle-class configuration (226 damn seats crammed into that tube). I'm not complaining. It's a great airline.
The Calgary-Keflavic leg is around 9 and a half hours long and the fifty-seven has not prob with it.
Los Angeles to Europe? Whewy! I'd hate to be crammed into a 757 for that long
144 config. is okay though, i'd imagine
Again... will look when i find the manuals.