Books of this type, I assume, are read by those who already accept the premise. But I don't think that only Christians read the Left Behind series and this would be a good book to read if they wanted to learn the concepts behind the story. It is a good primer on End Times prophecy with a minimum of preaching (which it does obliquely - homosexuals, pornographers, and substance abusers get a special mention).
This is not a scholar's book. It does not discuss translation or the use of a concordance. It uses various translations of The Bible when there is a quotation.
What the book does is present its thesis that the End Times will occur in the following way: 1) the conditions which must be met for the Tribulation Period to occur (mostly having to do with the geopolitics of Israel - it is largely believed that this has been met since 1967) mentioned mostly in the Books of Daniel, Ezekiel, and Isaiah, 2) The Rapture, 3) The Rise of the Anti-Christ, 4) the seven-year period of Tribulation, 5) The Book of Revelation with descriptions of the bowls, trumpets, horsemen, etc.
It is a frightening story and very provocative. I am not born-again, but I do find the subject fascinating. I think it is a great invitation to study The Bible and find what it means to you. And, in a selfish way, it is just fun. I mean, for a moment, let's just take its premise on face-value and accept it... it means we are all in for a real mess.
It is read in a straight-forward fashion. I have no complaints about the narration or subject matter. And I do wish it would find a larger following. It should be added that this belief is largely endemic to the United States. It is not mentioned in Catholicism (though John Paul II did mention it), Europe is largely secular at this point, and most Protestant sects do not go in for this either. Therefore, this is only going to be heard by the already converted. To me, that is a pity. It is a fascinating introduction to an esoteric subject.