I doubt the complain would be useful since CX has tried to fly the PAX to his destination, and tried to arrange hotel for overnight stay, though much time is wasted in the delay. (I will leave the delay part to my travel insurance.) These unfortunate events are really unforeseeable and unpredictable, you wouldn't want to fly a bird that is known to be leaking right? I guess the compensation won't be too high, hey, but who knows if your original ticket is booked in F?

I hope no one would swear not to fly CX again... Its really not their fault and CX is still quite dear to us in term of service right?

Last to ask, would you complain if you were in my situation when a KA 330 2 class config departed in a full load, originally only 1 PAX was booked in J and Y was very much oversold? (All the Marco Polo Club members including me were sitting in Y, because I have seen them in the lounge! Plane was delayed for 1 hour and supposedly those who has the access to the lounge will stay in the lounge. How could the J be filled up later with us all in Y? AND, I was the only Gold member and the rest were Silver. Unless those in front are Diamonds who checks in later...) I guess many would want to file a complaint in this case.. haha