We have done the Meal Deal and I personally like it. We're not heavy eaters by any means but have two teenagers. It is $20 per person for your "entrees" and $9 for the cup. So, it is nearly $30 for the day and does not include breakfast.
Here's how we made it a value: We got to the park after breakfast at our onsite hotel. Once, we got to the park we had lunch ($15 per person for us). Little later we got our mugs refilled, for we got thirsty ($3 per person). About an hour later, we had a small snack (fries, chips; $7 per person). Towards the end of the day, we had a big dinner ($15) with multiple refills (some locations at Universal now charge for refills). Overall, the day would have costed $40 per person without the meal plan, so we saved $10.
It worked out well, and the restaurants were okay. The nice thing as that they are strategically. At IOA, you have one in Seuss Landing, Jurassic Park, and Toon Lagoon. At USF, you have one in New York, World Expo, and Hollywood.