Regarding the risk getting the AF birds out of SIN, I got the information from a AY sales person. Reality shows that there is a quite good chance to get those worn seats from and to BKK as well.

I can t see how you can use your own head sets on the ex AF planes in J since the headphones are fixed to your seat - and they are not good.

I changed already about 8 tickets from AY to LH and TG because of the "old planes", even if they cost me about 30% more.