If you pick this up to watch a serious movie about life after a nuclear war, you'll give up on this in about 5 minutes. But if you like watching a movie that you can make fun of and groan at, then this is the movie for you.
As I was watching this I was thinking just how bad this movie was, but I kept watching to see what goof, inconsistency, bad line, etc. would come up next. And I was not disappointed.
You've got stupid people running around in the desert and guns that never run out (almost never) of ammunition. You've also got the chance of running into a radioactive rain storm, but only drive cars with no roofs. And much, much more.
This is a prime example that if you make the movie bad enough, but still entertaining, it will hang around for a long time.