You literally couldn't pay me to take Tiger, even just Syd-Mel.
If you take Jetstar it's a little more bearable but be prepared that you're traveling with people who think it's acceptable to bring a steaming dripping kebab onto the plane.
I always choose Qantas, even for those micro flights. It's probably the asshole snob in me, but I just don't find the cash savings make up for the tin can Jetstar shuttles you in, nor the people you have to deal with on the flight.
I took just over 120 flights last year, 110 of them were with Qantas, 6 were Virgin and of those 6, 5 were cancelled or otherwise encountered serious problems. Personally, Qantas all the way.