We flew Edi-Mel in February with a 1 year old and an eight year old. I was dreading the flight and couldn't relax for the first few hours. The eldest watched the tv for the majority of the flight and the younger one was fine throughout. Only problem we had was when she slept in the bassinet, we had to remove her during turbulence which woke her up.
Only advice I would give is, make sure you have plenty of snacks for the kids, this will keep them going between meal times.