Pros
I'm not really sure where to begin. My feelings on SI&A can be summed up by the fact that I never think to myself "I don't want to go to work tomorrow." I never dread coming into the office. Every day there is something new and interesting going on. One of the main aspects that makes SI&A so enjoyable to be at is that everyone else wants to be there too. Everyone has a smile and I hear people laughing regularly all throughout the office. People are always willing to help if you need it and your co-workers, managers & executives actually give a damn about you as a person. If you make a mistake, your coworkers and managers are there to help you fix it and learn from it without passing judgement or holding grudges. I have never worked anywhere that managers have cared so sincerely for the wellbeing of their employees. If you want to apply yourself and grow in your career, SI&A is a great place to work...I know that it's where I want to be.
Cons
I think that if you are someone that doesn't respond well to honest feedback, you may have a hard time at SI&A as feedback is given regularly.