Opportunity to work with various customers and if you're lucky you can have an interesting mission. The top management use to be very good at communication / manipulation. It is always inspiring to witness the effectiveness of their tricks.
Cons
Management doesn't care about you. They'll try to strech your resume as much as they can to make it fit, even for jobs you don't have the right competence or interest.
In geneva, they hire french consultant with very low salaries compared to the swiss market. Be carefull!