Wiki has problems mostly on current day political and social controversies, largely because of the byzantine bureaucracy being weak to infiltration by special interest groups pushing their views as "mainstream", but compared to the editing and peer review that documents like the Quran or the Bible were subject to (i.e, none, or by theocratic dictators and their lackeys), it is the essence of impartiality and objectivity. And that's ignoring the large, large portions of wiki that are edited by professionals that are on the top of their field, especially when it comes to science. Of course the social "science" subjects are a mess of conflicting propaganda and interests, that has more to do with social "sciences" itself than wikipedia. Let me put it like this, if you were somehow stranded on a desert island, or sent back in time 4000 years ago, which compedium of knowledge do you think would be most useful to you? The whole of wikipedia or a fucking Bible?