Pros
For anyone who just graduated from school with a business major KPMG is definitely one of the best places to launch a career as it offers various well designed training programs throughout each level of the jobs and the opportunity to gain plenty of experience in a short period of time. I haven't worked in any of other Big 4 firms myself but from what I have heard and the information I got KPMG's culture and working environment is relatively more lay back and easy going. Overall the management is pretty supportive in terms of the work/life balance and serious about maintaining a competent working environment.
Cons
The biggest downside of working at KPMG is the long working hours. Even if the firm management is supportive for creating a work/life balance environment sometimes you just can't find the time to have a "real life" due to the intense working load. So never try to compare the hourly rate you get from working here to others!