All of the above, and also Vietbus, are bound to present cultural differences. And it's a two way thing. We struggle to bridge it, but the women also struggle to bridge it. If they are going to migrate here to live with you in Singapore, it's a lot harder for them.
You don't know even ten words of their language to have a meaningful conversation with someone who is not a tourist you met at Changi Airport, or a native you met while holidaying in their country, but is your WIFE. How do you even help her to settle down in Singapore?
You just want a woman in your house to have sex with legally? Or you want to have kids, and expect her, who speaks either no or very bad English and maybe zero or halting Mandarin, to stay at home to raise the kid? When other kids start speaking at the age of three, yours can't even string a sentence to just say, I am hungry...and when your kid starts primary one, he is like a foreigner in the classroom in his own country, who is unable to talk to other children because his mother could not speak much with him, and he learned too few words.
The best women for a wife are still our own Singaporean women.