Pros
Charles River is a really cool place to work - the research is cutting edge and really interesting, the people are extremely smart, and there is such a broad range of work going on that there are constantly new things to learn about. There's a lot of room for growth, whether its technical skills, business development, or leadership roles. It's also a great size - large enough to have a support staff that is fantastic, but small enough that you don't have to deal with huge levels of bureaucracy and red-tape that is common at larger organizations. This also plays well with the personal growth and fast-paced research side of things. The benefits are fantastic, with great flexibility, vacation time, health benefits, and many other unique offerings.
Cons
Research isn't for everyone, and there can be projects that don't end up with a clear transition or success.