Before you even start modeling, you should probably create a morph target. I'm not home right now, but.....I think its under morph target tab, you click on create. This way if you plan on importing it back, the UVs and the base model won't get messed up and rearranged. If that happens, it makes UV'ing a little harder. Displacements would be fine because it would follow along the UV that you mapped out, but color mapping would probably get stretched. I'm experienced that a few times before I finally figured it out. Kind of.