I was just about to book this routing - depart SYD 7pm to BNE arriving at 9:30pm then taking the Emirates 23:30 flight out.
Then it occurred to me that if, for any reason, there is a delay out of Sydney on the Friday night (which has definitely happened on many occasions) then I would be sweating big ones hoping that I could land in time, get across to the International Terminal in BNE AND check in with sufficient time.
I could book the SYD-BNE leg separately, but I don't have the benefit of the great price (as I end up paying the separate one-way flight).
I could book the SYD-BNE leg via Expedia.ie (as it's not available on Expedia brazil), I end up paying the EUR price which is roughly the one-way fare, and it wouldn't help if there was a delay because I would have to book it as a multiple destination rather than as part of the one ticket (ie rather than QF being responsible for finding me another flight out of BNE if my flight from SYD comes in late, it would be entirely my risk if my SYD flight came in late).
So, having pictured the absolute nightmare of the thought of having to call Expedia brazil (in portugese) to change to a later BNE-SIN flight while sitting at SYD departure lounge watching delays on flights out of Sydney (rain/hail/fog/late planes - it's all happened before), I chickened out and booked the direct flight out of SYD. Stressful business this!