Simsy.....I haven't got a Rav 4 but if you own one i would be more than happy to give it a go for you!
My mate had a saying about 'A Break' in the wet....."One of the only places your wheels turn forward but your car goes backward!"
Been a while since i have been up there (few years now) but looking at taking my brothers (new to 4wding) up there soon for a day trip. Time they got some scratches on their soccer mum vehicles! Might actually find Dianas Bath up there this time as well.