I haven't given birth at HIAZ myself, so I can't share firsthand lah, but honestly it's quite a popular choice among mums around Bangi area, lots of people seem okay with the facilities and the staff there. If you're considering it, maybe join some local Bangi/Kajang mummy groups on Facebook? Those groups usually have recent stories from mums who delivered there, and they're quite honest about the good and not-so-good parts. Your gynae will also know the hospital well, so worth asking them directly about their experience working there too.