Hmm, looks like my decision is become clear. I think I will be sticking with my CBA Gold Visa for now as my alternate to my Amex Maximiser card. I also assume that if I continue to accumulate points on my CBA Gold Visa, and then later upgrade that card to Platinum, I will still get the 1:1 transfer to QF, even for the points I am earning while I have the Gold card (which only transfers at 3:2).