Pros
Mercer has great intellectual capital overall and vast professional resources to learn and service clients. Some profs are snobs unless you have clout, but most are a blessing. You get all the PowerPoint training you can handle, that is, training via PowerPoint. Bring your lunch and take good notes.
Cons
Leadership is very top-heavy and out of touch. Smaller clients are an afterthought and are better going elsewhere since they're probably not sexy or profitable enough. One has to track their time as a law firm (a NYC law firm), regardless of the revenue arrangement. Constant reinventing, re-branding, rehashing, re-something. Don't expect senior management to guide, train, or want to get involved. They are above that. Sink or swim until you sink. If you made rush in college, you'll fit in better than most. If you were GDI, good luck. Fit the mold or be gone. We want to listen to our clients, but let's deliver a 100 page presentation to talk about ourselves. If we don't, we'll get poor performance reviews.