Svdl is right on the mark on this one.  I am a follower of the VSS Prop system developed by Bagginsbill and it is top-notch.  And the nice thing about it, it's free!  Technically, it is not just a Skin Shader system, it's application could be applied to just about any prop, object or model once it is full developed.  But, in the meantime, it is a WIP with many devoted followers. 

The thread is rather extensive and will take a little time to absorb, but it is worth reading and experimenting.  Although you can use it with any human figure and texture, I have managed to create my own VSS Prop to shade the Nybras demon from DAZ.