I like using my commonwealth bank credit cards - 3 points per dollar spent on american express and 1 point per dollar spent on mastercard. I spend about 80k per year on the card to pay for business expenses and therefore get enough points for return flight to hong kong, business class. The annual fee of 250 dollars is very worthwhile - I also get complimentary travel insurance.
if you are spending 80K a year on the card regularly- you would be nearly qualifying for like the black titanium platinum american express invite.
american express is probably the best rewards card and the fastest in terms of response time and service.
I had so many flights from them just from paying my 20% deposit on propetry purchases, (DIMA) immigration fees for relatives etc which they paid me etc.