Pros
The people you work with tend to be really professional, very friendly high-achievers who went to the big four because they didn't know what they wanted to do after university. I think the department I was in was part of the reason I really didn't enjoy my job but I know other departments (like consulting) are apparently a lot better to work at. Also it does look OK on your CV
Cons
Abuse of highly skilled employees, high workload with very low compensation, very happy to dump as much responsibility on you as possible with as little compensation as possible. They lie about being willing to pay for your exams unless you are in the tax or audit departments (I was in the managed solutions department KMS). I know people who were there for 2 and a half years and they refused to even enter discussions about paying for exams. Also communication is absolutely abysmal, it took me 6 months to find out their overtime rate (13.37 p/h for anyone wondering). They want to keep you in the dark as much as possible about as many things as possible which sucks