I'd suggest starting with the P4s, just because they have fewer vertices. Duane Moody has made some great P4 morphs that I'd suggest getting and studying. Load in a few of them and then work them through the dials to see how they affect the head singularly or in groups. I think you'd be surprised what can come out of those two. There was a texture file called the "Vickybuster" that, when it's used with the P4woman and a few select morphs, makes her downright gorgeous. And I've always had a soft spot for the guy -- he's far more flexible to work with, IMHO, than Michael (although I haven't done anything with M2 yet). Look at any of the later Backstage images on my gallery, and you'll see what can be done with him with enough care and attention.