Originally Posted by
george 3
Have done this - while the two terminals are very long, it is doable since you don't have to go thru immigration/customs.
This is incorrect, You will go through exit immigration in T4S and then the additional US screening as well.
Still doable, though.
I mean, I try to get to the airport 90 minutes before long haul flights and still have a good bit of time in the lounge.