I'm going solo for 3.5 days in April. I looked at the menus of where I wanted to eat and picked the dishes I thought I might enjoy. I came out $78 ahead by purchasing the dining plan. (Ironic, no?

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If I wasn't drinking alcohol, I would not have purchased the dining plan. If you aren't drinking, it probably doesn't make sense. But like others have said, do the math based on what you would order.
Enjoy your solo trip!!!!