I'll echo what aster has to say...it takes a bit of work (no one killer card), but I think 2.5 to 4 miles per SGD spend is what atleast a fair few on this board earn (with some even better transaction & card specific deals). I don't optimize every transaction, but am in that ballpark - am sure there are others who do much better than me.

Sure the hefty sign up bonuses that some US cards give are a pipe dream for us here, but 3.4-5.4 miles/USD spend is pretty good imho.