Another factor is what aircraft type it is. Both airlines operate A330s and 737s on the route. A330s are generally superior with a 2-4-2 config down the back, but if not then Virgin with extra legroom on a 737 beats a Qantas 737 (except for the exit rows in the middle which you can pay for, or Row 4 which you might get T-80 when it gets released for lower than QF P1. If it matters, bear in mind all Virgin 737s have no seatback IFE, but the A330s do. QF has either seatback IFE or provides Ipads at every seat on the transcontinental routes.

However, if it were me (excluding the fact I get lounge access with VA through NZ, until Oct), I'd pick VA over QF with such a price difference, I'd buy extra legroom on the 737. Yes both come with checked baggage and inflight meals and drinks.