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.
How can you realize the freedom you have in Christ? I say that you will discover it, more times than not, in the midst of the bondage that still seems to hold you down. You see, the power of the gospel is not found merely in the words of its testimony of Jesus’ death and resurrection, it is found in the reality that has been brought about because of who he is and what he has done. That reality is that Christ is in you. He is there, and his life witnesses from within you … despite all the doubts that you think actually come from within you. source