If it was me I would also go with individual flights. Having a RTW ticket ties you to an itinerary which you might want to change at a later date. You might be able to change dates (for a price?) with a RTW but can you change airports?
For example, are you sure you want to fly direct from Singapore to Aus, or might you want to spend some time in Indonesia? Personally I would much prefer spending time in Indonesia over Singapore, but that's just me.
And I hate itineraries. I bought a half way RTW ticket once (UK - Aus) thinking before I set off that it was the best option but ended up not using half of it as I wanted to stay places longer than the ticket allowed.
So I guess it depends how you're travelling. If you're fixed on dates / places and that's not going to change then RTW might be good, but otherwise I would go with individual flights.