I think you are getting confused with how shaders appear in the preview and how they render. These are completely independent and each shader behaves differently. Genesis 3 skin uses the AoA SSS shader. This shader displays in the preview as if it has very strong ambient. I think this is suppose to be some simulation of the SSS, because if you turn the SSS strength down, it gets weaker. This preview has nothing to do with how the skin looks in the render.

Also the AoA SSS shader is a 3Delight shader. If you are using Iray to render, the shader is being auto-converted to an Iray shader for the render. DAZ Studio will not show you the parameters of this auto converted shader after the render, but if you apply the Iray Uber Base to the skin surfaces that is probably similar to what was used.

The DAZ Default shader is an older, more basic shader that is use for most props and some older characters. It does not support SSS and has a more basic preview. If you load a prop/character with only Poser material (.pz2) the Poser material is auto converted to the DAZ Default shader. This conversion is fairly good on older Poser material, but DAZ cannot completely convert the newer Poser material with complex shaders. The results with newer Poser material is hit or miss.

The DAZ Default shader is also a 3Delight shader. It is also auto converted to a Iray shader if you render with Iray. You can apply the Iray Uber Base to do the conversion.

When you convert surfaces to use the Iray shader, it will change how the preview looks, but Iray character previews mostly look shinny and are misleading as far as how things look in the render.

If you are using Iray , you can use the nvida Iray display mode in the editor window to get an idea how surfaces and lighting will really look. If you are using 3Delight, you can use the AUX view window and an IPR render to see how surfaces really look.