UV Mapping

Well, I've ran into a small hindrance with UV maps (how surprising). What I'm unsure about is whether or not I should overlap UVs - How does Mudbox deal with this? In particular, should I be overlapping the front and back of the cuirass that I'm working on?

This is probably something that should just be figured out the quick and dirty way - just try both. But as you can see, I currently just have the front and back somewhat next to each other, and I feel that it would be much much more efficient if i could just overlap them.