We spent 4 nights in this apartment. The flat is nicely decorated, clean and the staff very friendly. That being said, it is really tiny. The room can really just fit the bunk beds and there is not much left of the living room once you unfold the sofa bed. The sofa bed is also very hard and uncomfortable, to the point we almost canceled the rest of the stay after the first night.
Location wise, the beach is 10 min away, and so is the bus stop to Mui Wo, so that part is great. One thing to note, Ham Tin is surrounded by stagnant waters and mosquitos are all over the place, you won't be using that balcony much.
I guess all the above would be quite acceptable if the price wasn't that high. But a premium rate of 2000+ HKD, it's really not worth it. Would not recommend unless you are specifically looking at Pui O and no other options are available.