Genesis 3 has facial rigging, V4 and Genesis 1 & 2 do not. And all the Genesis models have a fraction of the poly count that V4 has, with G3 being the lowest, in order to make it more compatible with game engines (even though it will most likely require a poly count reduction, as 17K is still considered extremely high for a nude game figure in most instances. If that's 17K with a full set of armor and weaponry, then you're probably ok).