Pros
Flexible work arrangements. Great people. Great managers who treat their employees with respect. It's a highly ethical and thoughtful in its analysis. Merck is a company that prides itself on its diversity. I've honestly never seen as much diversity as I have seen at Merck. The corporate headquarters that I work has to be one of the best headquarters hands down. It's in the same of hexagon and has a park (a park!) in the middle of it. Having a stressful day at work and just need to talk a walk for a minutes. You just have to walk down and go to the park.
Cons
Not as much transperency as one would like in career advancement. My personal experience has a great manager who is willing ot help me learn anything that I need to or answer any questions that I would have. The trouble is that she's hardly ever there and is stuck at meetings most of the time. So basically training is next to a no show at Merck, but it honestly could be much worse. By far though the experience at Merck has many more positives than negatives. Working at Merck is a great experience. I work with some of the most competant, professional people you could find.