Melbourne to Brisbane done over 4 weeks.
7,500-8,000km done in total.
Started off with 350 to the tank but fixed that whilst away and was getting 550-600.
Would do it again but in saying that next time would love to take 4x4 and go more places and do more camping. (So not with the mrs next time lol)
Hotels and cabins get expensive along with 98 fuel.