I ate there some years ago, must have been at least 5-10 years. Personally, I probably wouldn't eat there again. Its something nice to do just once, to say you've eaten in the castle, but other than the "bragging rights" I really didn't take away much from the meal. Even with reservations it took a while for us to get into the restaurant because of the line to see Cinderella before you actually went upstairs to eat dinner.
I don't remember there being anything bad about the atmosphere, though undoubtedly the best seats are probably the ones closest to the windows, which we did not have. I don't think they did character dining back when I ate there other than Cinderella downstairs. I didn't pay much attention to this as we really weren't going there for character experience, we were going for the castle experience and the food. The food was probably the biggest letdown. First off, it was expensive. I don't remember what the rest of my party got, but I remember getting a dry, tough pice of prime rib that wasn't good at all. Three of us went and I think the only one that liked it was my sister, who was 6 or 7 at the time and really into the princesses. The adults didn't care for it.
Like I said, it might be a good restaurant to try just once so you can say you've done it. If you're wanting some five-star dining experience in a romantic setting for you and you're boyfriend, I think your two dining service credits would be better off spent at Grand Floridian's Narcoossee's.