We did lunch here last summer. The line seemed pretty long, but moved very quickly. I don't think we waited more than 15 minutes in line. I don't know if I would use up a FP for it.
The funny think about our lunch was that we walked around looking at all the rooms carrying that flower they give you. As soon as we sat down a server was putting down our food. She must have been following us through the rooms. I said. "Oh, no! You must have been following us around. I didn't realize how it worked, I am so sorry. I thought it would take longer for the food to come out for sure." She said, "oh, that's okay." I was thinking we needed to put up a visual, (like at Ghiradellis in DTD when we sat) And the way she said it told me she HAD been following us. And there we were, just taking a look around. Of course, she did assure me that it was just a magical castle and that is how the food comes to you as soon as you sit down!