Vantaggi
Xerva only does one thing - data. At most other companies, you have one or two other people in the company who do serious full-time data work. Not much of a community. At Xerva there is a lot of back and forth exchange of ideas, testing new models, and exploring trends in data processing and visualization.
Svantaggi
If you don't like data, you will get sick of all of the conversations about data. This is a company by and for data geeks. Which is a great thing if you are one of them.