The AA miles offer expires tomorrow - you get 40,000 miles for USD 1100 (about AUD 1280) and some 8 weeks later you get another 15,000 miles.

The one-way biz-class award on QF between any two places in Aus/NZ, whether direct flight or via connections (eg PER-AKL via BNE) is 17,500 AA miles, effectively costing you $430 each.

For MEL-EZE, according to the AA award chart for zone 2 of S America, it is 50,000 for one-way biz award and 100,000 miles return, sorry. But AFAIK this allows QF, LAN but also the indirect route via LAX and DFW.