I'm actually facing the same choice right now. All depends on what you are looking for. If you're an SO, its an absolute no-brainer to go for AC. Otherwise, its a bit more of a difficult choice. AC you'll be on flat pay for 4 years. Your monthly pay will be less than $25k HKD before taxes, so hopefully you got a good nest egg saved up. The variety at AC I think is second to none however, which I think is the huge attraction factor for me. Also there is plenty of movement right now so you might get a quick upgrade which takes some pain off that flat pay. Another downside of AC is if you end up on reserve, you'll have very little control over your days off. Something to think about if you have child-care issues. Good luck with your decision. I struggled with mine.