You will be amazed at the excellent attention you get while dining. My DDs are both allergic to milk. I felt so relaxed at every restaurant while we were at WDW. The chefs were great. The counter services took a little longer, but we were definately spoiled with all of the assistance we received.
The best was at Sci Fi ... the chef offered to make them soy milk milkshakes. My DDs are both still talking about them a whole year later.
Good luck. Sit back and enjoy dining !