Aiko 3 introduced some changes to the material zones for the legs, splitting them into sections, so you have to do some manual copy-and-paste in the Materials Room, but the texturemaps for A3 characters will work with all the V3-compatible characters. Not a freebie, but DAZ 3D have a texture converter program for about $10, which will open up the use of V2 textures. Dial-based characters interchange pretty well between the Unimesh figures. New Morphs depend more on the starting point. For instance, David and Hiro have a bigger chin than SP3 or Aiko, so a morph will have smaller deltas for the same end result. (moment of realisation: maybe it's possible to make an SP3->David morph without much trouble, if you have both figures. But watch fio height differences...)