Pros
Each of the Tempus buildings are very beautiful and look like something out of Westworld (particularly Chicago). The cafe and tea room offerings in Chicago are especially nice in my opinion. You will have some very educated (e.g. ivy league) colleagues, many who are particularly wonderful people to work with. You also have the option to WFH if you are not central to one of the main sites, which is something particularly beneficial in a post (perhaps still ongoing) pandemic world. Also by working in a late-stage start-up, there is still some flexibility for you to dabble into other departments and their initiatives should that be something of interest to you.
Cons
By far the most micromanaged company I have ever been a part of, and when this company says they are fast-paced and fast-changing, don't mistake that for chaotic. The leadership on my team was absolutely horrendous; would constantly be a wrecking ball to projects that were currently initiating next steps that everyone agreed to, weeks if not MONTHS afterwards (just because they were too busy to show up to a meeting or read any email updates keeping them abreast of any situation). It was an absolute joke having things change constantly with no thought put into the effort involved. Communication was beyond terrible with stakeholders having side conversations and not including the main team. All in all a very sophomoric culture at best. 9/10 do not be surprised if you have people on your team that know next to nothing about research taking on leadership roles, and you are having to handhold them. Guarantee you will lose your mind in no time. They also are a bit stingy on the hiring side; they would rather have existing staff pulled from other projects to allocate time to yet another project and limit their bandwidth even more vs. hire a brand new person. Also the benefits are horrendous here, no employer matching in 2021.