We headed out to Birdsville in August 2009 (2 Jeep Cherokees, 1 Grand Cherokee and 1 Prado) all towing CTs with the intention of doing the Simpson crossing E-W, but after heading (without trailers) over several dunes west of Big Red we made a consensus decision that the chances of getting into trouble were too great (and one of the party had recently had head surgery and still had balance problems which the rocking over the dunes aggrevated) so we went north and round to Uluru via the Donohue and the Plenty.
The Simpson crossing is still in our minds, but when we do it we will take a tent rather than the camper trailer. And we are all ( well 75% are) experienced 4wders. We made sure we had extra spare tyres and sufficient fuel and water, together with all the recovery gear (shovels, hi-lifts, MaxTraks, winches), HF radio, sand flags, etc.