Pros
I would find it hard another company which has the same strength of culture engrained worldwide. Everyone is relatively young, fun, smart and ready to work hard, play hard. You can expect to be given responsibility from the outset meeting some of the most prestigious companies and brands, being involved in recruitment or running workshops. If you perform well you will have the opportunity to develop very quickly into more managerial roles so career progression is great. Great international opportunity with a very open flow for people who have performed and express an interest in working in one of the offices across 62 different countries. Great fun in the office including performance based treats like cooking classes, boat trips etc as well as Friday drinks and you tend to have an annual all expense paid Kick-off in countries such as Cancun, Jamaica, Miami etc.
Cons
The nature of the company being private in a competitive environment means a lot of organisational changes, which can be disruptive. Although career progression is quick to those who deserve, it lacks some depth which I think can frustrate people who have developed quickly early on. Benefits are very basic in terms of gym/health/pension