Pros
Good name on CV? Not a lot of work once you understand how things work there? (depending on role - you may get unlucky).
Cons
No career. Or rather, only career if you find somebody really senior that really, really like you. Confused management, very few systems and processes, a lot is based on who you know and having the ear of high-ups. Big issues between the London office and the Nottingham one. Many (but not all) people in Notts are in a golden cage - required to do hardly anything, are well paid, but have otherwise no career prospects and they know they are stuck there. This makes many bitter and resentful. The culture is all about smiling, pretending to be kind but actually no desire to do good quality work, or to improve processes and ways of working. Being liked is more important than being good. TERRIBLE at dealing with HR issues (no respect for workforce when pushing for structural changes, many people end up with impossible jobs. HR won't do anything if you have a complaint. There is such a culture of "pleasantness" that if you complain you are the weird one.