I had a great experience at the Sanitorium and with Dr. Liang. Dr. Liang is a really great doctor and I completely trust her advice on everything. She is quite a straightforward person though and some people may not like that. But I really didn't mind and felt very comfortable with her.
With respect to the Sanitorium, I also had a great experience there. I know that there are some other threads on this forum where other moms have had not so great experiences with the nurses, but I found them to be very helpful in all aspects. They also gave me good breastfeeding tips and babycare tips. The midwives were also really good. So all in all, I have nothing to complain about and would definitely go back there for my second child.
As for whether or not non-Cantonese speakers would have difficulties - I myself am a Cantonese speaker and so is my husband, so I can't comment too much on that. All I can say is that there were other non-Cantonese speakers in the maternity ward while I was there so I don't think there really would be huge a problem. Do you speak Mandarin or does your husband speak Cantonese or Mandarin? If you speak Mandarin, it shouldn't be a problem as there were a bunch of mainland mothers there while I was there and I assume the nurses could communicate with them. If your husband speaks Cantonese it really shouldn't be a problem either as I assume he will be there with you most of the time anyways.