My kids LOVE Chef Mickey's. The food is pretty good, but the atmosphere is what's best. Be warned...it's really loud, but the characters really interact and spend a lot of time with the kids. We've been there four times - seen Mickey, Minnie, Chip, Dale, Goofy and Pluto. Never have been lucky to run into Donald, thought. That would have been a treat!
The service all four times was excellent. Be forewarned...maybe I just had bad luck but each time the coffee in the carafe was cold. Never a problem at Disney, however. Each time the server was cheerful, smiling and willing to please. I got a new steaming fresh cup without any hesitation.
One thing to think about if you have young kids...the monorail drives right through the Contemporary, just above the restaurant and my son (5 at the time) thought it was so cool. He thought it was so cool, in fact, when I thought he was right behind me at the buffet line he wandered off to see where it went and got lost. Scared me to death (him too). So...keep a close grip on your kids if they're into the monorail as much as mine.
las thing...one place I really liked, although I know I'm in the minority on this...is the Pooh bear character buffet at GF. We saw Pooh, Piglet, Eeyore, Mary Poppins, Alice and Mad Hatter. I believe price is about the same, but it is much quieter.
As with all in Disney...every choice will be great.
