hi Jay, yes i knew about that issue with FG you quoted already. its really not that hard, but it takes lots of fine tunning to get the right look. As you can see from the pics I have posted you can have too much SSS, or too little. Placement of lights play a huge role in bringing out the SSS. If using an HDR image you'll have to rotate it and possible add lights to make sure you get some SSS, or else you run the risk of there not being enough back lights to accentuate the SSS. And it all has to balance out.
I am so envious of your talent to produce those texture. oh well. The textures you use on your skin are freaking amazing.
Using SSS with FG/HDR is particularly tricky because MISSS does not have a way (that i know) of controling the color bleed you get from the HDR image. Other Maya shaders can be controlled using the incandescence color under the mental ray tab in the shader node. So what you may end up doing is modifying the colors of your HDR texture to get the results (color bleed) you are looking for. It really is a pain to control it all and find the balance which is why i think a lot of people stay away from it.
I will play a ltl more with the SSS shader on this guy, but im getting burnt out on him. Its defintely a learning experience from a modeling and a shader point of view. Next character should be easier