Vantaggi
There are not so much as "pros" to the job as "neutrals". The biggest takeaway is that you spend so much time with the people you work with that you end up becoming good friends. That could be in part because of the shared misery, and also because the company does seem to make an effort to hire people who are interesting. If you end up on a team of good, honest people, who are willing to engage in light-hearted banter to make the monotony of the day-to-day go by, you'll be okay. If not, and there isn't exactly a way to know going into the job, then I would advise steering clear. The one glimmer of hope I can give: If you apply here, NAFS QI team led by Andy Rottas is the place to be. A sensible leader, good people, and hard workers who are unassuming kind people, make this team a good cocoon for an otherwise terrible environment.
Svantaggi
Cons? Other than the company itself? The management at GLG is bimodal: excellent or terrible. In my position, I had both extremes. I started out with the worst manager I have ever in encountered in my entire life. Manipulative, rude, unpredictable, and unable to admit when they were wrong. I still feel my cortisol levels increase when something reminds me of this manager at my new job. On the other hand, the other manager I worked with was humble, understanding, and a great communicator, among many other excellent traits that you look for in a leader. As Forrest Gump said "Life is like a box of chocolates, you never know what you are going to get." Consider yourself warned. Outside of management, this at times mind-numbing, but always meaningless work, expected an outsized commitment to the position. Whether that be sending emails while on a roadtrip, responding to clients at 11 pm, or something else. There is not a moment of stress-free internal peace unless you've deleted Outlook. It's the type of company that says it is a "family" only because everyone is miserable and they don't want you to pipe up about it. Furthermore, the entire organization is clique based. That comes in the form of financial service teams vs. professional service teams; quantitative insights vs. client solutions; hedge fund client solutions vs. private equity client solutions. This leads to a semi-toxic working internal working relationship--far too many times did I spend hours a day dealing with stressed out, micromanaging, trustless client solutions members asking if I had done something for there one exact client. (For context, most Quantitative Insights team members balance 15-20 projects at any one time).