Pros
The people here are very smart and generally friendly to work with. This is a place that values learning and you will learn a lot, especially if you are coming straight out of undergrad and haven't made a deep dive into anything technical yet. And, depending on your group leadership, you can have a lot of autonomy and freedom in what you work on.
Cons
Management and communication are not great here. They promote people to management positions based on their technical skills, not on their management skills, which sometimes leads to very ineffective managers. People tend to work individually and not communicate very well, even within the same group. You really have to be proactive about communication here. There is also very little opportunity for advancement besides going to grad school and coming back.