I've always enjoyed time spent in HK and have many friends working there...the pollution is very bad...I operated in and out of there a few weeks ago and the pollution was so bad you could barely see the terrian around CLK...that's just typical winter time from what I'm told...vis 4000m in pollution...you really must see it to believe it...and before you can make an informed decision about moving children there.
I've seen plenty of days there where the air quality was quite ok but from what I hear that's only about 30% of the time. Plenty of people do suffer severe problems from the pollution...to say otherwise is denial of the obvious.
From what I hear on the grapevine KA guys are not all that happy...all the usual attacks on COS...all up I really don't want to work/live there anymore...quite happy with my jungle hideaway with clear air and a Boeing to drive.