Pros
Truly disrupting the market research industry with innovative technology and super-smart people, good work-life balance and WFH, impact is valued, very collaborative culture, modern technology and tools, embraces open-source, most leadership is very technical and "gets it," fun and challenging analytical work, the services team is much better than those at other companies to make sure client expectations are clear and wins are delivered.
Take the low-star reviews from Data Associates with a grain of salt. It is an entry-level role and can be a grind. However, many ambitious DAs have used the role as a jumping off point to get promoted to more technical analyst/engineering roles. If you're curious and understand you're getting experience with machine learning and data, you can leverage this opportunity.
Also pay attention to where the review are from, some of overseas locations have a different environment than the US. Lot of folks in Chicago & NY & SF love their colleagues and environment and jobs, and this is what is growing more within the organization.
Cons
The merger has growing pains of combining two different company cultures, but people and execs are advocating for what's best. HR and recruiting can be more progressive. The value of Vista's influence can be questionable at times. Office is fine but lackluster compared to other companies.