quick q - i am flying one way business from syd to london with cathay - is it worth signing up for MPC? i was thinking of just credting my points to qantas (no status either) i will be flying a few times next yr in economy frrom syd to london
Putting that one-way earn to Asia Miles/MPC will earn you 13,219 miles (including bonuses),
calculated here. On the other hand if you credit towards Qantas you'll earn 13,216 points and 140SC,
calculated here.
With CX you'll need 30k miles to attain/retain Silver, which gives you lounge access only when flying CX (possibly DragonAir too). Gold requires 60k miles and gets you lounge access when you fly any OneWorld airline.
On the other hand, QF requires 300SC to attain Silver and 250 to retain it, there's no lounge access included but you get one lounge pass to be used at a Qantas Club when flying Qantas. It's also worth noting you'd get 50% bonus on QF flights. Gold requires 700SC to attain and 600SC to retain and gives the same as Gold with CX, the bonus on QF raises to 75%.
In your case, I'd say you stand a higher chance of getting to CX Silver than QF Gold, which would give you lounge access when flying CX. Importantly you should remember that when you take the economy flights with CX, not all of them earn at the 100% rate, lots are 25% and those would make hitting Silver a lot harder, some don't earn at all. The difference in earn on QF would be from 140SC in business to 35SC in discount economy, but depends if the fare even earns too.