Very good book! I really liked 1st Edition of Promethean, definitely my favorite WoD line in terms of themes and potential for conflicts. Some people thought it was unplayable or at least hard to play with multiple people. I used to do great having 1-2 prometheans in a game with some werewolves or mages. Once this book came out, I got together 6 of my friends to start a campaign for, and it's been really good. There's more solid rules for what your pilgrimage is and while I'm a little iffy on them, they made it easier to explain to those who hadn't read the book.
The increased importance of the refinements and roles definitely gives the game a different feel. One of my players does feel that the roles are kind of constraining from a role playing standpoint, but once we talked about it all ooc, we found that the more constricting roles actually give great potential for personal conflicts in the game. Promethean 2nd edition is definitely the game to pick up if you're interested in personal development.
I feel it's important to note: everyone in my gaming group is in their early 20s. I'm a cis male, but multiple of my friends in the game are trans, one is genderqueer, and no one is straight. Honestly, we had been losing faith in White Wolf/OPP in terms of catering to our demographic, but the inclusion of the gender neutral pronouns in this book really made us feel like people gave a shit, which is good. Sure, we prefer the Ze/Zer pronouns to the Sie/Zir ones used in the book, but hey, it's something? We liked it. People complaining about the 4 or so pages the pronouns appear on really kind of rile me up.