We were camped at Carnarvon Gorge National Park (back when one could still camp there) in 2002, at the same time as Rob Grey was there with Wotzahellisthat Version 1. It certainly generated a lot of interest and comment. We were amused by one traveller, who walked all round it, looked up at Rob relaxing on his verandah and said "You win". We left the same day as they did and were impressed that they waited until all other departing travellers had left, because the purple vehicle would be so slow crawling up and down the track out, and they didn't want to hold any of us up.
His blog is brilliant.