Best environmentThe good thingsYou'll be trained to be accountable and responsible through big projects. They'll let you do your thing in accomploshing tasks. Also, great environment because of young colleagues and very cool bosses. Really great place to grow and learn.
The challengesWorking with a BTL agency will always require much of your time compared to other companies. But honestly, all the hardships will be paid of because of the learnings and experiences you'll get along the way.