Genesis/Genesis 2 are designed for DS, that is why they work better in that software than Poser.  DSON importer makes it convenient to port over Genesis/Genesis 2 from DS to Poser retaining much of their functionality and poses.  It is a compromise to extend the use of these meshes across 2 separate applications.  By all means, the conversions are not perfect.  Lags can be overcome by tweaking certain features, other problems may need DS to refine the issues.  

For example, my issue in PP2014 and Genesis 2 is applying genitalia to the figure. Always, the secondary rigged figure for the genitalia appear when conforming to the main character.  Essentially, you have two Genesis 2 figures, one poseable, the other not.  My workaround this problem, load both figures into DS, save out the scene in DS format, then import the scene into Poser using a 3rd party free app (Dimension3D's DSONLoader)  This is a little inconvenient, but it's the best workaround I can figure out ATM.  

BTW, I would use the term Genesis 2 rather than G2, G2 is a different set of models available from Content Paradise.