I just bought a house in Pegasus. After speaking to Tower and AA, I was quite surprised at the extent of the "Don't Cover" causes. My impression is the policies have been tightened post earthquake. Some random stuff like not covering damage to the shower drain. Which could occur in a quake and would cost heaps to address in a slab foundation.
If someone has recently has taken out insurance in Chch or know of any key pit falls, I'd be keen to hear about it.