Vantaggi
Reputable company. Nice people, including the CEO. Flexible working hours, opportunities to work from home occasionally. Possibly good career opportunities if you are lucky.
Svantaggi
Extreme favoritism. Things were going fine when I was fired out of the blue for vague "performance issues," despite the fact that my performance never seemed to be a problem when I was working on weekends to help finish projects or meeting crazy client deadlines. They'll get rid of you right in time to avoid paying your bonus and leave you with no health insurance and no outplacement assistance. If your manager likes you, you're immune from this treatment. To be fair, I think this could depend a lot on what group you are in, but this was certainly my experience.