Vantaggi
Prior to BTL, I worked for a language school in Paris that was so disorganized and no one seemed to care or want to help. BTL was the opposite. They are very hands on and meet with the teachers regularly to provide helpful hints to better teaching. They have a department dedicated to planning our classes, an Admin team who take care of student cancellations. Management is nice and always willing to help. The other teachers are cool. They have a teachers' room filled with pedagogical resources, computers and printer. We each have space to keep our books or student files. They even organized a nice Christmas party. I made friends at this school.
Svantaggi
Because they care about their students, they ask the teachers to take time off during the Parisian school holidays so that we are away the same time as the students. There are so many holidays in France that it seems to work out OK, but don't expect to take time off whenever you want. They run their school professionally so they expect teachers to be professional in return.