There is another issue - driving long long days will have you tired right when you need extra alertness - in the dark!

In my younger days I actually preferred driving at night - no more. When I'm traveling cross country just to "get there" I hit the road about 7am and drive till dark, and get a hotel. If you need to push the envelope you may want to consider adjusting your schedule to hit the road at "zero dark thirty" and calling it a day when it gets dark. It's also easier to find a hotel room at 7pm than it is at 1am.