Why would you go to a city uni to do ag science?
By far the best place to do ag science is UNE at Armidale, they have Ag, Rural science, Livestock science, Agronomy, Agribusiness, Agricultural economics etc. Plus you are in the middle of prime agricultural country with sheep and beef, only 1 hr from intensive livestock at Tamworth, broad acre cropping out west, dairies at the coast. What agriculture is at Sydney? It just seems silly to move to the city to learn about something in the country when by far the best (and easiest) option is in rural areas.
Then there is Charles Sturt, which is pretty good, they have ag, horticulture, wine making, equine science, agronomy etc.
It looks much better if you have done a rural based degree in a rural area, unis such as UNE have pretty close to 100% employment for B. RuralSc. grads as they have a good reputation for agriculture.
Really doesn't make sense to go to sydney.....