We did it in October for our anniversary. I highly recommend it! It's such a once in a lifetime experience, food was excellent, view was fabulous. It's a bit pricey but so much nicer than celebrating something in a park or resort restaurant. They ask you your likes and dislikes as far as food goes and the chef prepares a menu just for you. You are on a balcony overlooking the lagoon and the GF pool and to the left you can just about see the top of the castle where you can see wishes. We also saw fireworks from Illuminations and the water pageant. We had our own private butler who was great. We had a lot of alone time. They serve a special dessert during wishes.
If you get the chance to do it, I say go for it!