Pros
Design is king; extremely talented, smart and fun people; high-quality work; good benefits for a design agency; competitive pay; growing agency; slowly improving work/life balance. VSA is very very good and loyal to those who have either started their careers here or have been here for a long time. Managers vary but mine were great about protecting the team and making time whenever you needed to talk. If you're lucky, you will get to work on some really fantastic accounts. They are sweat shop/boot camp if you will, but they have a system in place that enables them to do really great work and make a lot of money doing it.
Cons
Even if you come in with a few years under your belt and work hard to prove yourself, you will not see any sort of promotion for a few years. Management is stretched very thin and is constantly changing (since the company is growing), so you get shuffled around a lot which means no one has been consistently monitoring your performance. Great projects and opportunities go to the same people/teams pretty consistently. Project managers are a redundancy and act like gophers instead of articulately advocating for the team. Client expectations are sometimes set in such a way that teams get completely demoralized.