I was at OFT last June, I concur that you definitely should get your written exams done first before flying out there, you need to be at the school taking every opportunity to fly that comes your way, not studying for exams.
Last year there the 152's were booked up far more than the Pipers, of which I believe thay have more. The folks flying the Pipers were streets ahead of the 152's even by the end of week one.
Be aware that you are intending to fly during the hurricane season, this cost me *two* whole weeks last year. I'm told winter time is much better for flying in Florida.
If you're not happy with you're instructor, shout. My first instructor was clearly not happy and either left or got the boot after my week 2. The first thing he had said to me after introduction was "If you've got a problem with me then, come and talk to me, not anyone else."....not a good start. 2 weeks later he was gone. The 2nd instructor was great.
You will need to look after number one and push them to get you up and flying, they will not do this for you, you will not complete a 21 or 28 day course if you don't keep on top of them. If you're not happy......shout!
Get written confirmation of the accommodation situation before you go. Some students (myself included) were being told that accommodation was included only to find out at the last moment (and were already committed)that they had to pay for their own hotel room. For this reason alone they will not be getting any more of my business.
Have fun, and Good Luck !