I am not a member of CX or SQ FFPs. But I use both extensively on longhaul (and CX also on regional). I understand the frustration with some aspects of either airline/FFP. But IMO both CX & SQ are outstanding airlines compared to most others. The CX forum has many op complaining about some aspects of CX and DM status (a few threads on the benefits of DM), and the general impression when you read the CX forum is that SQ is superior, although I find it more expensive. Eventhough I am not PPS or DM (but BA emerald and BD Gold), I have found both airlines to be responsive to my needs and problems. I use BAEC coz 1) I fly also in Europe 2) BA FFP is more generous than CX 3)BA treats is top customers well. But on the small OW alliance I found that other OW airlines tend to recognize Emeralds and treat them OK, plus you get F lounge access worldwide. On the huge *A, there seems to be little recognition by other airlines and no F lounge access. That suggests giving priority to a OW FFP like BA or CX.