;)
It is better to start at FL 410 as that eliminates all but most of the traffic. Hence no bug smashers to watch for and other slower traffic to get of course for. And regularly checking your performance for next available FL in your FMS, will give your range a good boost while sipping fuel. After FL 470 it really is lonely up there but quiet and the more direct routing helps as well. O2 is an issue, and compliance mandatory in our ops so we keep the engineer busy refilling the bottle after our long legs across.
The difference? Bragging rights and we do NOT glow in the dark contrary to popular belief.