The question about which FFP is good for discounted airfares really depends on which airline you are flying on the day and intend to fly in the future. QF is good with discounted flight credits when flying on their flight numbers. On the other hand, QF FFP only awards 25% of the miles when travelling on BA's Economy class.

If you provide more details of your itinerary and airlines that you are wishing to patronise, then we can provide a more clearer recommendations.