I've never actually been in a Dunking Donuts restaurant. The restaurant is clean, has a nice lounge area with tables. I do have to say that the service was very slow, and they were already running out of Donuts at 1000 am. I'm not really into Donuts, but I came with a friend. Overall experience was just ok.
Update: Brought the Donuts home and they tasted stale. Never going back again!