I was lucky to get a full six players, all of whom where fans of the books. Only one person was familiar with FATE (via Spirit of the Century), but even with having to explain the mechanics to everyone it went very smoothly. Everyone seemed to love the system. There was some concern about the Mental Stress cost of evocations prior to actually playing, but honestly there wasn't any problems with it during actual play. The magic was epic but serious injuries were sustained (one of the Wardens picked up a Severe, Moderate, and Mild Physical Consequence all in one hit from an Elder Gruff). Everybody was happy at the flexibility and, as per the game rules, we went with "describe what you want to do and figure the system out afterward" and it worked great. Nobody felt the magic was underpowered but, as stated, there were definitely real threats. Some notes:
1) I was impressed at how much variation I was able to get with six Wardens. Between Aspects, specializations, and careful spending of the couple free points of Refresh led to six very different characters: an Unseelie Changeling, a shapeshifter, a houngan marked by Baron Samedi, a master of fire magic, a swordmistress, and an ex-cop. Similarly, nobody felt like there character was underpowered compared to the others, even those with a couple mortal stunts instead of extra supernatural powers or Refinement.
2) I was very happy with how the Social Conflict went. It was an interrogation scene with a Red Court Vampire and showed off well the integration of role-play and mechanics. The Wardens got most of the information they wanted before the fire mage incinerated him out of vengeance, but realized later they had missed out on some key bits of information. The mechanics definitely made it easier for me, as a GM, to run. I've always had trouble imposing rolls on social situations and have been uncomfortable with how much is left to arbitrary GM judgment in the social sphere. It feels better for everyone when you can say "his Discipline defense roll easily beats your Intimidation roll, so he laughs off your threats" instead of just saying after fifteen minutes of menacing RP "he laughs off your threats because he's a badass" and having your PCs feel that their efforts were wasted because you'd already decided he's not going to talk.
3) I can't express how much I love the magic system. It is versatile without being arbitrary, combines all of the elements of magic in the books (gathering power, tiring, losing control) into a single roll, and integrates focus and enchanted items in a really cool way.
That's all I have for now. Happy to answer any questions or queries.