Hi David,
I have been on it and can highly recommend it - having had the pleasure of being the Tour Manager for the tour 4 times!! Everything being equal I should be the TM again in October.
It really is a fantastic tour. You'll see and experience so many things: from the obvious - Sydney Opera House, Uluru (Ayers Rock) and the Great Barrier Reef; the cute and cuddly - koalas and kangeroos; through cities to countryside in its colours of yellow, red and green; the surprising.... but I shan't tell you these as they won't be a surprise!
Happy travelling,
Sarah