Pros
Working for the firm will definitely boost your resume however there are a lot of things you will have to deal with while working for the firm. For a public accounting firm, PwC pays alright, however please don't be swayed into believing the pay is amazing, as you will be able to find if not the same but better outside the firm. The firm is a powerhouse and you will work a lot, however if you are smart you make sure to absorb and experience as much as you can before flying the coop. Also, make sure to bargain during ARC compensation meetings.
Cons
Like I've said previously, the firm is a powerhouse. With that said, there are several reasons or downsides to working for a large public accounting firm such PwC: long hours, busy season, an even longer busy season, managements constant pleas to convince staff the firm is the best place to work and that there are no real problems, managements determination in attempting to make staff feel the firm is superior from a compensation perspective, the world behind the not so clear arc process, seniors who think they are managers, managers who think they are partners and senior management who could care less when staff come and go.