It is much more the latter than it is the former, but I would classify it more as a cautionary tale in many ways. That is, the "good guys" don't really win.
For comparison, Fahrenheit 451, 1984, Animal Farm, and Brave New World present cautionary examples in a fictional context, but can still be seen as political works in their own right.
This is not to say that you'll enjoy the book (it is a long book, and anybody who has read it will remember the 70-page speech by Mr. Galt, even if they ended up skimming much of it) or even agree with the philosophy; often it seems that well-intentioned approaches that result in disaster by the "bad guys" (e.g. job security measures -- nobody can be fired) are disastrous only because they are taken to an extreme (e.g. everybody gets paid the same).
As for why I would recommend reading it, I grew up in the 80s, and I feel like the view I got from reading most casual fiction of the time and even from my early education was that communism (especially Soviet-style communism) was as valid an economic system as capitalism, and in the future imagined by scifi authors, the USA and the USSR were side-by-side in the conquest of space; and that much of the anti-communist sentiment, and the Cold War itself, was more of the Dr. Seuss "Butter Battle Book" argument over which side of the toast should be buttered, or pointing out specific leaders of the USSR (like Stalin) as being aberrations, rather than an indication of problems with the system of governance. Reading Ayn Rand (and later, Goldwater's Conscience of a Conservative, and various works by von Mises and Hayek) gave me a more complete view in a lot of ways as to why the Cold War happened (even though most of those books postdated the start of the Cold War significantly), and how McCarthyism could have existed in a country that to my young eyes seemed extremely tolerant to controversial ideas.