There seem to be a concensus that gold or Zirconia is preferred for the second molar and beyond for their strength and being out of sight. What about the lower first molar? The tooth is largely out of sight except under fairly specific situations. Would the shadow in my mouth mask any aesthetic advantage Emax has over Zarconia? Are all full contour Zirconia identical or do some manage better aesthetic without compromising strength? MPa and aesthetic aside, are there other factors to consider?