Vantaggi
The company culture at AEI can't be beat. Especially among the entry-level employees, there is such positivity in the workplace that it makes being at work much more enjoyable. Because all the entry-level employees are within 1-3 years age of one another, and because many of them are DC-transports, everyone is social and looking for friends. Hard work and good results are extremely valued at AEI - it is definitely a meritocracy. If you work hard and complete quality work, you will be recognized for it. Arthur Brooks and David Gerson (President and Vice President, respectively) truly care about the employees and have a strong commitment to the values AEI stands for, and it's evident in the way they run the ship.
Svantaggi
AEI is most definitely a political place. Regardless of being officially non-partisan, they are 100% conservative, Republican, neo-con, etc. If that side of the spectrum is not where your viewpoints lie, it can be a stifling environment. Your experience there also heavily depends on the department in which you work. In conferences and development departments, the work is menial. Your function is purely to secure donations and make AEI look successful - very nonpartisan, but boring. In the policy area departments, it very much depends on who the Resident Scholar is. The hours are long, crazy, and the work never, ever stops.