Pros
The IMF is a great name to have if you're interested in economics or macro. There may be no better place to learn the basics in an academic type multilateral environment; if that's what sounds appealing to you, look no further. However, with a BA, you'll probably end up leaving for grad school or somewhere else. If you enter with an MA, you'll eventually have to leave too for somewhere else. There are no long-term career options in my opinion. They basically kick you out after 4 years being a Research Analyst.
The job takes 4-8 months to get used to (semi-steep learning curve) but once you're there it's fairly easy day-to-day. Economists are nice. Bosses are reasonable. No major demands, no overtime (for me). Boring infrequent social events. Can start working 9-10AM and leave around 5-6. No opportunity for travel (to go on missions) in my department, although others are better. You get some research experience/exposure, but I doubt they'll publish your name as an author unless you're really good and have been there a while. They'll probably thank you in a footnote or something.
People in DC are impressed when you tell them you work here. It also offers flexibility in terms of how you can sell yourself for the next position: i.e., you can make convincing pitch for "I'm a quant guy", "I can do macro/econ" "I'm great in multilateral environment" "I'm meant to work in government" "My skills are relevant to Wall Street/private sector" "I'm a development professional" etc. You can really pivot in a lot of ways in your next interview, and sell the IMF experience however you want.
Work is fairly independent. Things are done on teams in theory but really everyone works on their own on a minute by minute basis. Great opportunities for macro/econ/IT/statistical/econometric trainings for free. World class lectures on hardcore econ stuff.
Cons
No long term career path, but hey I don't want to stay in DC anyway so not really complaining. Plus you should probably have a PhD or lots of work experience before you get hired as an economist. So don't expect this to happen after being a research analyst for 2-4 years although it is possible (and some people make the jump but they're very good).
