We made the reservations a few months ago. I believe they had been closed for maintenance so it was pretty wide open. That being said we did have to change campsites every single day which was a royal pain in the ass. We stayed in site 5 one night. It's fine, nothing good or bad about it. If I were to go back I'd stay at a site around #30 it was the only site with good shade and coconut palms on both sides. I meant to write down the number but I never got around to it. I'm sure if you called the ranger and asked for the site with coconuts on each side they'd know which one.
I've now stayed at all the state parks in the keys. My first choice for camping would be Bahia honda, followed by curry, then long key, finally Johnpennecamp.