" Friends did that trip recently. The vehicles were worked hard and needed lots of trackside repairs and welding of broken bits.
A major logistics operation, run well from the client's view though. It was very expensive"
Had one of their groups turn up at Durba Springs when I was there last year on the Canning, had a good talk to the tour leader and some of the drivers, also showed us all the vehicles, it took them several years to get government permission to use the 6WD units. They have a team of Mercedes mechanics operating out of Newman who meet them somewhere around Georgia Bore to check and repair the vehicles.
They have a couple of groups of vehicles as we again caught up with one of the drivers from Durba Springs at Hall's Creek as he was setting out on another tour.
Ended up meeting some of the mechanics much later at marble Bar, not sure of the truth behind this, but the mechanic claimed the purchase of the 6WD wagons was allowed so the army could evaluate the longevity of all of the various models of G wagons based on the reports compiled by the Mercedes mechanics, he also said the vehicles needed a lot of repairs, but you need to take into account, the Canning is not a forgiving trip if you don't look after your vehicles.