What I found is GraphicsMod has way more options than DHH but is an absolute chore to make shit look good if you are not familiar with what everything is. Also has SSS. DHH is pretty easy to use. Not too many sliders but no SSS.Try both. Compare. Decide by yourself. ;-)
They can both make things look amazing in character creation. Then you go in-game and it all falls apart. Just the look you can get in character creation doesn't even compare to the in-game, which is weird.