On the topic of "eat first," I think this is good advice not only because of the mediocre quality of United's food, but even more because the flight leaves so late at night! When I have done this flight, a good strategy is...
- Grab some decent food near SFO. If you're not from California / western USA, you can go to In N Out off the Milbrae exit. There's also a Panera right there, and if you prefer, there's an El Torito, Elephant Bar, and Benihana on the other side of the freeway. Have an alcoholic beverage with dinner if you can - skip dessert.
- When you get to the airport, go to the international first class lounge and have another drink.
- When you sit down on the plane before takeoff, get a movie started right away! It is nice that you can start the movie right at the gate.
- Skip dinner... you just ate... But have another drink...
- Enjoy some cheese and crackers when they bring them out.
- As bad as United food is, they do a great ice cream sundae... So eat that!
- Have another drink...
- By now, you should have finished a movie and had a good meal before the flight with a nice dessert, and plenty to drink! It will also be about 1:30AM California time, at least....
- Pass out in a very comfortable bed seat.
- Wake up for breakfast en route to Sydney.

So I actually think UA's product is just fine for this route...