Having recently done two long sectors on QF and two on BA in J, I think I can make the following observations.

* QF upstairs cabin looks better than the BA one
* QF catering better except for dessert, BA still lead there
* Booze is much of a muchness, both have good selections
* QF staff generally friendlier and nicer (except for Mussolini in Micromesh from SIN-SYD), BA staff slighly more professional.
* Skybed is a better seat for me than NCW bed
* NCW bed is a better bed for me than Skybed (I'm 6ft 1in)
* Upstairs is nicer than downstairs, but it is a bit noisier.

I would happily fly either again and intend to.