Find a Din Tai Fong. Some of the best dimsum I've had. It comes out fast and super consistent.
If you go to Victoria peak, take the tram up,
Do NOT stay in Chunking Mansions. All the scum and villainy of HK is based there. You will be harassed and pestered everyday for custom suits, copy watches and all kinds of drugs and prostitution at night. Stay closer to Mong Kok, it is the best of the night markets.