If you're a point to point, O&D passenger on the LAX-PHL route, the timing of the middle flight is particularly appealing. Not leaving until 3:40pm Pacific time--that would allow you to have almost a full work day in LA but still get to Philly that same night.

US's last flight to PHL is almost two hours earlier, since they're trying to get to PHL in time for the last bank of express connections.