Pros
A truly awesome place to work if you are genuinely interested in Data Science. The management is really great about understanding what your interests are and steering you towards opportunities that match them. The company has a core set of DS related projects at various agencies, but also a very lively R&D division which is active in expanding the company into new and interesting technical disciplines, and if you are interested in some specific niche that is related in some way to client work, you will probably be given resources to pursue it. The focus on professional development is really unlike anywhere I have ever worked. Pre-covid, on Fridays, everyone would meet at the main office and spend the entire day working on fun R&D side projects and professional development, and I expect this to continue post covid. The fact that they let us take Fridays mostly off from billable work to do professional development and share knowledge says a lot about the company. Also, when you are in between client projects, you get to basically pick a data science related thing you are interested in and get paid your salary to learn about it full time. At lots of consulting firms, you are a cog in the machine, and your employer tries to squeeze every billable hour out of you that they can get, but this is the complete opposite of the culture at ERI.
Cons
Not many that I can think of - I did not like the transition to WFH, but this had nothing to do with the company, and I think was difficult for lots of people. The awesome thing about ERI is the culture, and it felt like it just wasn't the same with everyone working remotely, but I fully expect that once we can all start going to work again things will continue as they were before. Also, if you aren't into the constant learning aspect you might not fit in well, I think it is expected that the technical employees have interests and professional development goals that they want to pursue. This was not a con for me but could be for some people.