First, as futurelawyergal mentions, you shouldn't plan on transferring. Grades are very arbitrary, and you very well might not have good enough grades to transfer.
Second, how much more would you owe if you went to Miami compared to FSU, when you factor in rent, food, etc.?
Edited: I failed to notice that you said UM sticker price v. FSU in-state.
I agree that this is a no-brainer. FSU is your best bet.