I agree The Mandibles is not playing in the top league of dystopian novels, but it still contains some nice ideas as well.

I liked the fact that in the end of the novel the border to Nevada was rather a propaganda line and not a death zone. Don't trust, verify. Do not believe the lie and do the work and verify for yourself if you can escape the prison land.

I guess from the dystopian novels describing the economic breakdown of a society Atlas Shrugged by Ayn Rand does the best job.

However you can observe threads from all the mentioned books in this article in world today: 1984 (surveillance), Brave New World (escapism), Fahrenheit 451 (censorship) etc.