IB is internationally recognised. The only problem is once you are on IB, it's difficult to convert back.
If you are sure that your kids will study abroad for university, then IB is a good choice (as they usually treat the HK qualification as similar to UK's but HK's exams are much more difficult). However, if you go for IB and intends to stay in HK for university, would have to go for non-JUPAS route, which is more cumbersome and the chance of getting into good subjects is less than the JUPAS route.
