I have been flying to OZ upstairs on UA for years. Meals are as others have posted above - the snacks should be out for many hours, they vary but are mostly packaged stuff like chips, shortbread etc. Sandwiches sometimes are out, sometimes you ask.

One intangible: the route seems to draw some of the most senior FAs, which I personally appreciate. They know what you want and you get it. Ask for a G&T and you get a full set-up for two etc. As always YMMV. A couple months back, I had a long and fascinating chat with the purser about her career going back to Pan Am in the 1960s.