Pros
I'm writing this to share my opinion about Vatic, having previously worked there as a Market Scientist, which I left for personal reasons not really related to the job. Nobody at Vatic has asked me to write this review. The number one asset Vatic has is its people. In my life, I've had the chance to work with (and in some cases, lead) groups of really smart people - Ph.Ds in math, computer science, physics from top schools, in a variety of fields. Among these, was my time at Vatic, which has assembled some of the brightest talent I've ever had the chance to work with. In addition to their raw talent, the team at Vatic is extremely down-to-earth and nice to be around. That shouldn't come as a surprise, since the group has developed and actively maintained some core company-wide values that stress camaraderie and respect. Working with this team, you'll learn a lot - from state-of-the-art machine learning, to high-performance computing, and when interacting with Jim (I did so on a daily basis), you will learn so much about the industry and the trade. It's also a two-way street. Jim is enthusiastic to learn about machine learning and how to effectively apply it to trading.
Cons
Nothing major here. Vatic is a young company and (I believe) their management style is evolving. When I was there, the mode of operation was more tactical (day-to-day) than strategic research, which was somewhat disorienting to me, coming from academia - but that's more of a personal preference.