What is the Difference Between an Express Console and an Express With Emphasis Face Panel?

Nothing is different except the software installed when it ships,paint color, and the addition of a 4th DMX out port.  
Hardware wise, these are the only things that changed.  It has all the same guts. 

NOTE:  EMPH-EXPN face panels (Black Emphasis face panels) will revert to Expression 400's when loaded with 3.1 Expression code.

NOTE:  EMPH-EXPS facepanels (Single Scene Emphasis Express facepanels) will revert to Express 125's when loaded with 3.1 Express code.