While it hurts me to agree with anything Watchdog said......
That is true about the fares.
My Wife recently flew to Melbourne and back, so before she went I checked Virgin Blue online as I presumed they would be the cheapest, then I thought I may as well have a look at Qantas, and to my amazement Qantas were actually some $20 cheaper than Virgin Blue.
So needless to say she went Qantas.
I never even considered Jetstar of course, as I still love my Wife.