The mapping is completely different on all four P6 figures. They aren't texture-compatible with any previous figures (or with each other, for that matter), and Dark_Whisper's Universal Texture Convertor utility doesn't support the P6 figures yet.

A few texture sets for Jessi are already available, mostly here and at RDNA.

Morph-wise, I think the figures have some potential. However, other than expressions, they don't have a lot of built-in morphs. You'd almost certainly want to invest in the head and body morphs sold at RDNA and Netherworks Studios.

Also, Jessi has some known joint issues out-of-the-box, and there are those who consider her physique and proportions to be unnatural. Jim Burton has spent considerable effort retooling the figure into "Glamorous Jessi". You might want to visit PoserPros and take a look before making any final decisions.