Congrats on the acceptance
Regarding choosing a school: it is a very underrated-ly difficult part of the med school application process. The short answer to your question is that there is no answer that someone else can provide.
You have clearly worked hard to be in the position that you are in now, so you should take some serious time to make your decision. Try making a list of the pros and cons of each school and see if that helps. While money is clearly an important factor (15k/yr x 4yrs), it should not be the defining factor. What is it about each school that draws you there?
Remember that med school is 4 years of your life and if you are not happy with your surroundings/curriculum, those 4 years are going to seem like a really long time. $60k is certainly a lot of money, but if you are unhappy then it is unlikely that you will be able to perform to your abilities. If you are at a school that you like and entering a field that you love, you will work off that additional debt without a problem.
Everyone has different things that they look for in a medical school, factors that are uniquely important to that person. When I chose to come to Case I "went with my gut (heart) feeling", not my wallet. I could have gone to schools that were cheaper and schools that were more expensive, but in the end I came to Case and I am so happy that I did. To be blunt; I love where I am,
who I'm around, and what I'm doing, plain and simple
In summary, my suggestion is that you sit on your acceptances for awhile and really think about your motivations for each school. Talk to students at each school and find out what they do and don't like about their schools. And finally, attend the "second look weekends" for each school in the spring. Not to over-hype it, but Case's Second Look was convinced me to come to Case.