Advice: Stay mid-market or try to get big 4?

Currently, I just finished my junior year of college and I have an internship with a mid market firm for next spring. I will be graduating that same spring with my bachelors in accountancy and will have my 150 credits to take the CPA exam. Assuming that I receive a full time offer after my internship, would it be worth it to decline the full time offer to try to get a job at a big 4?