It is OK. The room is small that is kind of predictable. An even smaller bathroom is also acceptable. The reason to downgrade the rating is the length of the bed. It is merely OK which means not enough. The worst point is that the end of the bed is the wall, and thus it is impossible to leave your feet out. Trust me, any person who is taller than 175cm/5ft9 will feel uncomfortable when sleeping. But if it is not a problem for you, and you have a limited budget, I would recommend this place. At least it is not bad.
PS. It is not such cheap concerning with the area and supplies even in Hong Kong.