Well, I would have to say the Dakar (but I am biased).
The Dakar was obviously not as fast on the motorway through Spain, but the others were happy to cruise at 80mph (at least they said they were).
None of the bikes suffered any mechanical failures.
Zmeagol had problems with his Jesse luggage, Dfor had a recurrent loose indicator mount and Bigrob's adventure developed a strange desire to lay on it's side (reducing the fuel capacity of his tank slightly!!)