ZRH I spent one contract in HK which was just over 3 years so this might be of help.In our case the pay was according to previous experience with the top of the ATCO 2 scale at about 79000 HKD before tax(15% max).You got an accomodation allowance on top,but most of that was used to get something decent as rents are very high.Also a travelling allowance for annual leave.Contract length was 3 years with a 25% gratuity at the end.You could apply for extensions on that or another 3years.
Leave is 28 days for under 40's and 36 days for over 40's plus casual days;1 for every completed month.They have a very complicated way of doing the leave and very creative ways of screwing you on leave.Need I say more!
They are persuing the localisation policy because it's Civil Service policy so new expat jobs are non existent at the moment.I left on very good terms but I couldn't get back if I wanted.Also it all depends on how the Chinese like you,and it doesn't take much to get a black mark.
I don't think the localisation policy is going well at the moment as the locals are having problems on Approach,but no doubt any rumours of expat jobs will hit this news stand first.You could always ask Civil Aviation Dept,HK and see what they say.As for working and living there,well it depends on who you ask.Some would quite happily see the place nuked and are there for the money.Others love the place and are having a great time.I really enjoyed it,but 3 years was enough of the pollution ,noise,congestion etc.Depends on what you make of it I guess.
I believe there are/were two from HK in Skyguide,so they might help you more.Hope this is a help.