I would choose QF A380 over the BA 777 or 747.
BA has a good product but the aircraft used on the Australia route, in particular the 747, are getting dated and who knows if you will get the new F class.
The A380 is a beautiful aircraft and the QF suites are very comfortable. Onboard service is a little less formal than BA but very friendly and the catering and wine are far superior.
Some people have mentioned the noise of people walking past but I have never noticed it. I mentioned it to the crew recenly and they said that there has been an instruction put out to reduce walking through the cabin.
The F lounges are superb in both Melbourne and Sydney.