Vantaggi
The best thing is the nature of work--I think they do some pretty interesting stuff out there. Reading Psychology and Management texts for a living is sure a great way to spend your work days if your interests and aptitude aligns with it.
Svantaggi
But work is not all there is to a company. Culture matters. Leadership matters. Work/life balance matters. It is a bad sign when people keep touting the culture at a place; culture is something that is silently imbibed and cherished, not always boasted about on the premise that most employees are young and "cool." It is a bad sign when most managers in the company are in their late 20s. Nothing against youth per se, but it takes certain experience to attain people skills. It is a worse sign when the most successful people in the company are almost always taking work home and working till 2 AM. It shows what kind of behavior is rewarded at the place.