One of the most formative events in recent memory was when friends of ours, very scholarly in biblical matters, and deeply respected, turned to Roman Catholicism and made it integral to their Christianity.
It made me examine everything I ever knew, with the view to asking the question, "Should I do the same?" And while I gained a new appreciation for things Catholic, the answer, after years of pondering, has been a most emphatic no.
I suppose the central reason for that "no" among many, is the lack of any foreshadowing from the Gospels of the edifice that comes to mind when we think of Roman Catholicism. "I will build my church, (my assembly, my gathering)" does not presage St. Peter's Basilica or the enormous, quasi-military power structure that headquarters there, however you slice it. The Papa, the Vicar of Christ doesn't remind me at all of the one of whom he is supposed to be Vicar. I speak not of his personal life, of which I know nothing, but of his function -- he administers his organization, he is not known for casting out many demons and raising dead people to life. But, you might say, Tradition, the "line that runs off the end of the page" has taken us here and therefore it's right. Well I think there's more than a inkling that that line has wandered considerably and even erred at times (we're only human after all). At any rate, it is a legitimate argument that if the end result is so different than the beginning, exclusivity cannot be claimed-- that other end results are also possible.
I maintain that the Roman Catholic church is a cultural expression of the Roman empire expressed through medieval values. Which is not a problem -- cultural expressions are a fine thing in my view. They just are not normative or exclusive. Which means that other cultural expressions -- post Renaissance individualism, tribal collectivism, and so on are equally valid. And I don't have to give my allegiance to the pope.