The one at Annerley was excellent.
This was a bit ago - but the one I attended was by a no-nonsense Canadian who had worked as a paramedic. Very practical stuff on choking, drowing, CPR, when to call 999, hands-on instruction, etc. A bit scary, but very useful. I thought so highly of it that I took notes and then taught the basics to my husband and helper. And I'm thinking of bringing my helper w. me for a refresher course.
Don't confuse First Aid / CPR courses with generic antenatal classes, which may be different, and cover everything from prengnacy to labor techniques. I took a TERRIBLE antenatal class from what I thought was well-regarded expat name. (I'm not going to name and shame here). It was basically a two-day rant against the HK medical establishment and a sales pitch for natural birth. Actually I am FOR natural birth, but I didn't want to be lectured. And there was very little hard medical advice, and no first aid or babycare element. So be careful what you choose.