I used this in a class for college students. Played a bit crunched in an hour and fifteen minutes, but they enjoyed it! There was some confusion over the descriptions of "our world," what the Fissure looks like, do we choose one fissure, are we just magically there, etc, but by the end, they were playing more smoothly.
For context, we had played Two Rooms and a Boom and For the Queen before FONT.