We did in April. We showed up around 3:15 and we were seated right around 4PM. No issues. It was wonderful - the staff was "fresh", we got to meet Master when he came out (beast) and the service was definitely the best we got in the entire parks. We had a ton of fun - we asked for a picture with "just the kids" (as in, just the kids with Beast) and he started to walk out of the sitting room area - the CM's played along and explained to "Master" that we meant that we wanted a picture of the children with just him, not just the kids in the room. We had a really great time interacting with him and they got lots of photos with our photopass.
There have been mixed reviews here on the restaurant boards, and I know they get busy. But it was one of our top restaurants in the parks. Food was amazing. They accommodated our daughters allergies, even for dessert. I got to try the grey stuff.
Our other "great" restaurant was Splitsville of all places. It was fun and fantastic. We also did Cindy's table and we felt that Cindy's table didn't even compare to BOG for us it just was very routine.
We also did Akershus character dining and felt it was horrible - we had some pretty bad mishaps there, and it was a birthday meal for my DD. The only thing I can say about Akershus is that we loved the Ariel there. She was pretty amazing and we really liked her. She came by twice and tried to make sure to spend extra time there with my kids (we were celebrating my daughters birthday), and she took some special time with my little boy. She came up with some super cute things to say to him on the fly about his custom shirt and she was pretty witty. I liked her.
BOG as a walkup early in the day for dinner was GREAT! Try it, it is worth it.