Re: How would an superheavy stable element be used?

You may want to check out The Wonderful World of Atoms and Nuclei for one laboratory's explanation for why they do what they do. I will try to summarize here.

Initially, research was driven by the desire to create new materials: new fuel for reactors and new metals with unique properties. When scientists realized that these superheavy atoms would be extremely difficult to produce, this led to increased interest in nuclear theory, and predictions of binding energies and the like. Experiemntal verification of these theories will in turn tell us more about how matter is created in stars and about the distribution of matter in the universe.