For a city of its size in Asia, HK isn't polluted.. Just look at the sea, hiking area and beaches... all decently clean...
Yes, I have only 3 issues with HK, the rising cost of living, tiny living space & impending death of 1 country 2 policy system.
I prefer living in Asia... love the food, weather during the evenings, night life, entertainment, boutique shops, etc... I'll soon be posting about what I prefer in Canada/Malaysia.. hehehe