I definitely think that Singapore has a better environment for raising kids, houses are bigger, public playgrounds are common, less pollution, better public school system, more relaxed environment. While Hong Kong does possess one attractive quality... $$$=better pay. Hence the 'dog eat dog' environment, I do wonder whether the higher pay is worthwhile...as you just tend to accumulate more materialistic rubbish in order to compensate the stress and guilt ...
Children's upbringing in Hk is also more focused on 'extra-curricular' activities, for example learning the piano or a musical instrument is often considered a basic requirement. Come on, this is the first place (and I have lived in a few countries) that a 'portfolio' and 'resume' is required for a young child to get into a school that has a half decent curriculum. Not to say that education in Singapore does not have its problems, but it is definitely less stressful for both parents and kids. And at least you do not need to pay thru your nose in order to put your child thru quality bilingual education. Will like to go back if I can ever convince my husband.