Seems to be a unique and interesting idea and I hope it works.Then it can be tried in other countries too. But I have doubts on its safety. Looks like it will take the most damage during an earthquake. Yes they have used a steel reinforced concrete for the outside walls but still I doubt its effectiveness.Besides the inner walls may take lot of damage during an earthquake and there is lot of danger of one or more of the units simply collapsing.
Take a look at this landslide
Now imagine some people having their houses built in such a mountain. There will be serious loss of life. There is danger of getting buried alive