What does she want her next 4 years to be like? Which school will come closer to meeting that ideal?
How does she want to spend her time? Does she want a more competitive or collaborative environment? Does she want her school community to be central in her lifetime? Some kids with very focused interests have more freedom to pursue those with a singular focus at a day school because they have no obligations after classes end. They can go to the barn, ice rink, studio, etc. to ride, skate, dance, etc. Other kids are thrilled to have so many options within 5 minutes of their room and love that they no longer have to choose between the theater productions and lacrosse.
From your point of view, what is the impact financially? Will the money you save from the full ride make different college options available?
It’s hard for us to advise you because this really is a decision that is more about your priorities than the schools themselves.