Actually Bonnie, that's an update to the original Project Evolution. I just think Erogenesis is planning on getting her into a couple more stores than the original product is, and included updates.
That said, I was on the beta team, so haven't purchased her, and I haven't played with her since getting the new PE One. I can say she's about dozen characters in one. IOW, you would select each of the characters as you would a morph, so that's nice, but as far as creating clothes for her goes, even though he included a couple of files you can use while fitting clothes for her, she has an unusually high amount of JCMs, so it's not an easy project. I created a nice simple dress for her, and I haven't done anything with it, except as a dynamic dress, because I'm what you would call a n00b as far as creating conforming clothes goes, so I haven't wanted to even try. From what I understand, the fitting and weight mapping needs a lot of patience.
Other than that, it depends on what you're looking for. As far as the price goes, compare it to getting a character such as Dawn, and then buying a dozen character sets for her. PE One would probably come out cheaper in the long run, but whether it would be worth it, that depends on how much work you'd be willing to put into creating things for her, and I don't know how many clothing products are already available for her.