Think very carefully
Have a real good look at what they are offering (or what they aren't)
I would suspect that with a command slot in a regional in Aust it would take you at least 5-6 years in Cathay before you even get close to equalling your current wage with the regional. Cathay has had one payrise in the last ten years. Don't underestimate the little CPI increases that your current EBA gets.
Don't under estimate the costs of Hong Kong. Simple things like a litre of milk costing 30HKD or approx $4 AUD when spread across everything you buy start to really blow the budget after a while.
Good luck with the Deliberations however remember that Cathay is a company that is recruiting on it's reputations of the 80's whilst not publicising how it's driving the conditions down in this century.