Last August it was about 2 hours at 7:30pm. They were backed up and we didnt get seated util around 8. We were finished with our entrees before getting summoned by the Queen, but it was before dessert. Waited a full rotation before Dopey came around. The characters seem to only be out for about 10-15 minutes, then do some song or dance, then disappear for 20 minutes before coming back. It was probably our longest character meal of about 8....but that was just my experience. Im sure many get in and out much faster.
Moral of the story, the later your dining reservation, the more they are backed up. It ***could*** take 2 + hours.