A JSON Library Evaluation for Java EE applications

I have a need to enhance a set of Java EE applications to support mobile development projects.   As mobile developers seem to prefer JSON formats to XML for passing data to/from mobile devices, I had a need evaluate current Java JSON libraries for use by the supporting Java EE applications.  The client prefers open source products to vended products.  The most prevalent open source product choices seem to be the following:

Json.org – (http://json.org/java/ )Google GSON V2.2.4 –...