I've read both, and the Urantia Book makes more sense by a country mile. The Urantia Book paints a rational picture, where the Bible paints a confusing, and non inspirational picture of the nature of things. The Urantia Book has only been around since the early 1950's.
Can you imagine what the attitude was when people first read the first Bible ? Most could never understand it to begin with. From what I understand the Bible was not meant for the common man. It was meant for the leaders of the church not the everyday Joe looking for Truth. The Urantia Book might be a hoax, but it sure seems like a more inspired book than the Bible. Give the Urantia Book a fair chance, and I think you might be surprised as to it's content. I was.