Pros
Young professionals get exposure to PR at top notch client companies, along with many lesser known companies. Opportunities exist to work o a wide variety of client types and industries. Benefits and compensation are good to very good, opportunity for travel and there's even global "work abroad for a year" program.
Cons
Easy to get siloed in a group or on a large account, but Edelman has improved opportunities for employees to transfer teams and onto new accounts over the last few years. Lots of egos and internal competition among offies, practice areas and individuals. Squeaky wheels tend to get a lot of grease, deserved or not. Lots of big egos. Still a pink collar ghetto, with the vast majority of upper management jobs held by men, though arguably slowly improving in this area. Expectation that you are "always on, always connected" can be burnout. Definitely not a 9-5 place.