Rjer,
I would strongly suggest you NOT bring your children to Hong Kong. The air and water pollution here is extremely serious. I left H.K over three years ago because of pollution related health problems. Within six months of returning to Canada the condition was improving and I now have no signs of the previous problems. Though I'm sure the damage is permanent.
Are you willing to risk serious health affects on your entire family just to fly a big jet? Would you take up smoking a pack of cigs a day for the same job?? I know you need to feed and provide for your family but there really are better places to do it. Good luck, it's a tough decision
Here's a link to the pollution index for H.K.
http://www.epd-asg.gov.hk/english/current/current.php