Pros
Some of the best reasons to work at Epsilon are (some of) the people are great, the work life balance, and the generous time off. The difficulty with reviewing a company this large is that each team and each location is very different. Some teams have more work life balance and others will work you to the bone.
Cons
Cons, like benefits, are unique to each team and each location. Senior leadership can be toxic and totally out of touch with employees. I know of multiple, amazing people that have left because they have butted heads with one powerful senior leader who refuses to change. The Publicis Groupe is an agency holding company, not a marketing technology company like Epsilon. As such, the agency teams can be very difficult to work with and they are not willing to learn. They promise their clients everything even when the juice is not worth the squeeze or what they are offering makes no logical sense. The data sales team does not have the greatest strategy or planning, no roadmapping, and only has the vision to look one month ahead. Fortunately this has been changing over the last year but the person leading that change just left the company. Engineering is difficult to work with and refuses to devote resources to lines of business that are growing rapidly.