Vantaggi
Finn Partners has a great reputation and touts some cool benefits, including free lodging in upstate NY ski town. Very smart people and exceptional clients.
Svantaggi
Because it is a mishmash of many different smaller agencies that they acquired there's a lack of clear vision, policies and processes for client services. It tends to be focused on billing, not results, in my experience. Some practices are much better organized and managed than others, but there's no clear communication or process about how the various practices can and should work together. There's a lot of territorialism since the various groups have their own P&L and, while they tell clients they have vast capabilities across practices, there's little incentive to collaborate.