When I found the series I read the four books in two days. I would have enjoyed books 3 and 4 a little more if I hadn't read them back to back. I think the author writes well and the scenario seems possible. We just have to look at disasters in this century alone and see where people go crazy trying to survive. There are looters, robbers, murderers right now, they don't just disappear because there is an apocalyptic event.
There are wise and unwise people in all positions, from the poor to the rich, from liberal to non-liberal, from healthy to ill, from .....etc.
We have been moving away from self-supporting since the industrial revolution and far to few are prepared for a world without electricity. The Red Cross website lists contents needed in a short term survival kit. Search the web for prepper 101 to get an idea of what might be required for a longer period of time.
I also believe there will be people like Carly - although it seemed a little unrealistic for someone who faced being a single mom, going to school, multiple jobs to survive being that self centered.
I look forward to, hopefully, book five. I would like to see more about techniques to survive, including drugs found in nature, planting ideas, multiple ways to purify water, starting fires, etc. Everyday things just to survive. A good read.