Frankly, I think all overnight flights from the US to Europe are miserable (and I've done it a lot), no matter which airline you fly. Flying back is much easier, since it's usually in the daytime. And unless you are flying back to someplace like NYC, you will be stunned by the one-way fares. Try for a window seat so that you can rest next to the window; a middle seat is the worst, and in an aisle seat I can almost guarantee that someone in the other two seats will disturb you mid-flight when they have to get past you to use the restroom.