From experience while travel to south east asia over the last 20...

From experience while travel to south east asia over the last 20 yrs, 20 yrs ago when the retail market open up at malaysia, Macro was the dominant retail force there where everyone pay for a membership fee similar to Cosco. Fast forward 5 yrs later, Carrefour was the dominant where no membership required and purchase goods in smaller quantity. Then 5 years after Carrefour dominance, the Giant super market combined with small scale retail shop lots is introduced and currently still the major dominance force in Malaysia retail market.

Judging by oversea experience, Cosco probably wont be the dominance force for long if consider the average Australian family size is reducing compare with Woolworth. Also Cosco required large large parcel of land for for its hypermarket retail concept to work, so it maybe more suitable for Australia non SYD, MEL cities and regional area where plenty of land are available yet relative close to working families.