Seems like a good deal to me, only an extra $10 for all of your food all day long, seems like a great deal to me, unless you can get admission cheaper elsewhere. The all day dining by it's self costs $32.99.
Yes its a real good deal. Pay gate price for your tickets and get all day dining for free. All day dining allows you to get one entree, one side/dessert, and a drink (if you buy a souvenier mug you can use your drink credit for refills) everytime you go through the line. If you just want a snack and drink then you can just get that and no entree. Your choice everytime. We always get the all day dining cause it saves us money. There are only two restaurants that you can't use all day dining at Dine with Shamu and Sharks.
When we were at SW over Christmas week, breakfast was served at Voyageurs Smokehouse. But I have read that the breakfast restaurant changes from time to time, so its best to check the park map on the day of your visit to double check. I believe the other locations which may be serving breakfast are the Spice Mill and Seafire Inn.