NIV? Tricky as far as the Greek texts used.
To me, it's akin to the Catholic Church using Latin until a while ago (and some wanting to bring it back). As a child, I knew all the proper responses to the Mass, but hadn't an idea of what the priest was saying or what I was saying - it was useless to me and I never got the message until many years later and was sitting in a non-denominational church. I was baptized, had my first communion, and was confirmed, all without a clue - following rituals does not save a person - even though the NIV and others may have some background you disagree with, the fundamental message of God's Love and Christs saving Grace rings loud and clear.
The NIV (and the NASB to a degree) have redacted New Testaments, because they used corrupted manuscripts. This goes back to the 3rd century, when people were already taking offense to the gospels and other NT passages, and changing them to their liking.
The manuscripts used for many modern translations were assembled in the late 19th century by a couple of "intellectuals," but the Textus Receptus/Majority Text were put together by Desiderius Erasmus in the late 16th century. The TR/MT are used by the King James translation.