I don't know about UF, but at my school which has a pretty big/competitive rush we are allowed to take two juniors as "freebies" meaning they won't count towards our quota. I don't know if UF does this, but it's worth looking in to. Because not many juniors go through rush and since we have 14 sororities, that means there are essentially 28 free spots for those girls. I dunno, just something you might want to check out.
