Pros
FM Global is truly a classy company. The benefits are out of this world. The company is extremely stable (both financially and employment wise). They care very much about their employees. Most everyone is extremely nice and helpful. While working on my MBA, I reached out to a managers outside of my organization (who had no idea who I was) for assistance with assignments and they would assist me every time. When I was interested in moving to another area of the company, I set up time with people and managers (again who had no idea who I was) and they sat with me every time. If you have the right attitude, you will go far.
Cons
You will go far if you have the right attitude... and have a lot of time to wait. Things move extremely slow. While the benefits are amazing - the pay is not great. Middle management is not empowered to make decisions. Often times when I would ask for a training, for example, my manager would say that they'd have to check with their manager. Low performers are not dealt with - leaving the high performers to carry the slack (for no more pay). Again, the benefits are amazing and the company hardly ever lets anyone go - so low performing people stay for a very, very long time.