Pros
Overall, colleagues are kind, intelligent, driven, good to work with. In theory there is also the chance to work on lots of interesting issues.
Kontras
The organisation has grown very quickly over past 5 or so years but the structure has remained the same. As a result there are loads of people who are not happy with their roles/ level of seniority etc. There are people (who are actually really good at their jobs) who have seen their level of responsibility fall as their level of experience has increased. This problem is made worse by a tendency to recruit in at the very senior levels and recruit people with too much experience for junior/ mid level roles. The end result is that loads of the staff are unhappy about their level of recognition/ seniority/ promotion prospects. Which leads to quite a bit of office politics.