MIT is the premier engineering college in the nation if not the world. With a student/faculty ratio of 3/1 you will not only be in small classes with world-class faculty and facilities, you will be around your intellectual peers. The undergrad population is only 4,500 compared to the larger public institution UMD with 30,000. MIT has a massive endowment of $17 billion. You will thrive at a place like MIT and is the reason you were chosen to attend.
Someone said if you plan on going to graduate school it doesn’t matter where you get your undergrad degree. That statement is a fallacy that is thrown around negligently on CC. 4 years at MIT is life changing and the actual education you get will stay with you the rest of your life no matter where your career takes you.
Cheaper isn’t always better and as you mentioned you will probably always regret not attending a world-class institution of higher learning like MIT when you had the rare opportunity to attend.
Good luck to you.