Pros
One of the most savvy, professional and cohesive organizations that I've experienced. From top to bottom, the company culture is rooted in transparency, creativity and hard work in service to the mission - exceeding customers' expectations through technical/product excellence, customer service and sound business practices. The company has put in place a solid foundation for growth and is well positioned for new and exciting opportunities in a huge market. There's also the strong sense that people like working here and with each other - a very collegial and friendly office. People focus on doing great work and don't bother with office politics/drama.
Cons
Consistent with the culture, C3 employees work hard and sweat the details. Getting it right is very important - but is well rewarded. This fosters close collaboration between peers and management, but requires some adjustment from other technology company operating environments. Personally, I think the tradeoff is warranted and is paying dividends for C3, but it can reduce risk-taking by individual contributors unless that facet of the culture is similarly embraced.