I do this all the time (although never to Oz), for 'transit security' it's definitely not a problem. Came through 10 days ago and I don't think I even needed to take electronics out of my bag, I think some of their scanners are this new type which can see 3D (like they have in AMS now). Can't remember 100% sure as I was in F and the lady who accompanied me on the buggy and through security did everything so fast that it all sort of passed me by. But I definitely had an F kit in my bag and did not have to take it out.