It probably would be a harder decision to leave SQ, rather than SIA Cargo, as SQ has more leave, better overall package and a more stable roster.
We had one chap who recently joined SIA Cargo aged 60 from SQ - he resigned half way round his first COP.
Actual bond is Sin$142K, decreasing linearly each month to zero, 5 years after completion of final line check. You have to put $56K up as a bank guarantee within your first month of joining. Most banks charge about $5K for administering the guarantee and you pay all the charges at set up.
