I got a full tuition Duke scholarship when I entered the MDiv program in 2009, so the field ed money was just a really nice bonus (if you do the math, the pay is absurd... something like $60/hour for church intern work). Many of my friends were on 1/3 or 1/2 scholarships, but used field ed money to shore up the remaining tuition they owed. Some folks still had significant debt, but I didn't know a single person who regretted enrolling. I know I would have gladly paid to study with Jeremy Begbie, Stanley Hauerwas and Reinhard Huetter, among others. I wouldn't blame a soul for choosing to go to Princeton, Yale or some other well-funded school. But if Duke is your top choice and you get in, I highly recommend trying to make it work financially. There is no better theological faculty in the US.