From my very limited J trips on the Oz to LHR route, both BA and QF have similar meal standards, volumes, taste and timings. They are code-share partners as well so I would be pretty sure that management tries to make things pretty much the same. There will be subtle things like pre-ordering breakfast the night before (QF do, but don't think BA do *). FA attitude varies on both airlines - some are absolutely great and are a credit to their company, some just do their job - like any employee!

Of course the seats are different and so is the layout (see other threads on these).

For me, I'd go with the longer seat as I'm tall. I'd support alect's remark - try both!

* -- hey - is this a QF innovation?