How much is too much for your MSN?

Is the cheaper school still a very good school with a good reputation? Do they have a program that would give you what you need? If "yes," then I think it is probably good enough. It might be just as good of a school, but cheaper only because it is a state school. The expensive one might not be any better. It might be more expensive only because it is a private school and receives much less support from the government.

So ... the real question is the quality of the schools involved and whether or not they will give you a quality education -- an education that will be well-respected. You didn't give us that information in your post -- but that's the information that counts the most.