Pros
EF is full of people who are passionate about education, and it's a great place to either develop professionally or to cut your teeth if you're new to the profession. There are really supportive materials with plans provided and loads of supplementary content, but you still have the freedom to get creative and teach your students, not just the syllabus. The onboarding is excellent; you know you'll be taken care of in terms of getting into the country and setup safe and sound and get on with exploring the country. Particularly in smaller cities, the salary is more than enough to have a very high standard of living and travel extensively. I've learnt so much, have had so many opportunities to develop and grow, and the vast majority of my colleagues over the past few years have extended their stays, moved up through the network of schools or taken up senior positions at other educational institutions, none of which would've been possible without EF's support. You really do get back what you put in - if you expect to come for a holiday, this isn't for you. But if you're motivated about starting or developing a career in education in a new country, EF is an excellent choice.
Cons
While everything was spelled out very clearly before I arrived, having to work weekends was certainly restrictive in terms of socializing outside the network of teachers at our school. Summer intensive periods can be very challenging, though you can see great progress from your students which is very rewarding. A comparitively low salary compared to public/international schools, particularly in larger cities.