Is that $9000 each year, or $9000/4 for $2250 each year? How useful would that UMBC $9000 merit scholarship be to you and your family? What are the requirements for maintaining it each year? Run the numbers for both places here: http://www.finaid.org/calculators/awardletter.phtml
If you were my kid, I would tell you to follow the love. UMBC offered you direct admission for your major, and a scholarship that is more than just pocket change. Go visit again. Talk with the students and faculty in the department. If you would be a commuting student, try the commute. See what you think.