double manning can be a good place to work, you do not have to do 4.5 hours, you can do 3 then change, its up to you and how long the journey is, most of the people I toured Europe with were competent drivers which would allow you to catch up on some sleep, if the scenery became a bit samey, most of our work was short term contracts so when boredom set in it was off to another country, or around great Britain if you had upset the boss, even some of the traffic jams in other countries were a pain ( especially big road works projects) but none as bad as running up and down the m6 or a12, our jobs were very seldom tight on hours so in all a leisurely paid trip around Europe with usually good company to eat meals with and view some wonderful places,