Avantages
Springbox hovers around 50-60 FTEs. It is the right size agency where you really get to know your peers and learn a lot from each other. Also for the size agency, employees are fortunate in getting to work on very big brands - PayPal, Microsoft Advertising, Disney, Dell, Nestle, Nokia. I've also found because of the size, the organization is relatively flat (less hierarchy). If an employee has the right mindset and tenacity, you can easily establish yourself and gain a lot of first-hand experience working with senior marketer clients and take on additional leadership opportunities. Lastly, you get to bring your dog to work on Fridays.
Inconvénients
If you don't like wearing multiple hats, being flexible, and at times having undefined aspects of your job, this is not the place for you. Like many environments, it is what you make of it. Also the agency focuses heavily on culture-based interview questions. Your personality really needs to be a fit here in order to work well with the other team members.