The NIV is (IME) the most popular bible among progressive Christians. It is clearer than most, and more positively written. On the other hand, the translators deliberatly altered some passages to 'correct' contradictions.
The problem, then, is that it will differ from the Hebrew texts more greatly than some other bibles, and that most fundies claim the KJV is the one inerrant bible (completely without justification incidently - I think they prefer it because the archaic language makes it easier to twist for their purposes).
If your looking for a Bible to read as a Christian, I would say NIV is one of the best, if your looking for one to read as a Scholar, or an interested party in the E/C debate it's to be avoided.
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