I think maturity plays a bigger roll than age though currently
SO is 5 years older than I am.
I guess it is tougher in Singapore to accept a younger guy when
you're younger because you're out working/studying and he is still
serving the army. The things you talk about, the people you mix
with, the environment is so different.
However, I don't think it is that much a difference when both
parties are out in the workforce working.
Just my 2 cents