For our tour, we just noticed on bikely, that you can look at an elevation graph, which kinda scared the hell out of us...
Have a look:
( Move mouse over the Show menu, then Elevation Graph )
It seems to be 7000m climb in the first 480km.... where does that get graded in the 1 to 10 in difficulties? Me and ang dunno if its tooooo difficult to do fully loaded or not..