Do you use the New American Standard Bible mostly?

Yes, I use the NASB. The main reason for that is simple: its stated basis of translation is accuracy and not readability. NIV, on the other hand, states that it chose an easier-to-read phrasing when the literal wasn't as easy. Consequently, there are numerous passages in the NIV that are really messed up because they translated them according to certain popular beliefs. That doesn't mean that the NASB hasn't also screwed up a few verses, but it's nowhere near as bad. And if you'll make sure to get a NASB with marginal notes they will show some places where the notes will show the literal rendering of a word here or there which has been very helpful to me.