I prefer hearing the person's voice so that I know their emotion through their voice and know how they feel. It is important to know how the person on the other line feels so that you can respond accordingly. In texting, they can respond with a "yes" but what they really feel like saying is "no". At least when you are talking to the person over the phone, even if you cannot see their facial reaction, it could still reflect in the tone of their voice how they feel. I really prefer call over text especially if it's an important matter.