Hong Kong was the first stop in my itinerary, before the start of an awesome 5 weeks of backpacking through the Philippine. Hong kong is relatively small city and very well connected by MRT. All you need to cover Hong kong is some information about the highlight of the city. I spent 3 days in Hong kong which was enough to see what I wanted to see, but you can certainly stay for longer. Once I was in Hong Kong I realised that, many people fly to Taiwan from here. Its only about 2h of flaying plus Taiwan is very cheap compare to Hong Kong from what I was told and its worth the trip. However I did not have the time to go to either Taiwan or Macau. You can do them two if you have more time.