My BI team is looking for a source control solution. Based on your experience with Azure DevOps and Bitbucket what would you say are the pros and cons of each, and if you had to choose based solely on source control which do you believe is the better solution?
If you are looking for CI, BitBucket is not the preferred solution - it has many limitations that Azure DevOps does not have. That being said, GitLab is probably a superior solution to either as it has a very sophisticated and flexible CI solution and you can even run your own CI workers if you need access to resources that aren't available on the hosted service: such as specific hardware, very long run times or licensed software.
Other than that, if you are only interested in source control, and specifically git - either will be a good offering as well as quite a few others. You do need to make sure that the software you plan to control is a good fir for git - specifically, if you are looking to store large data sets (I'm thinking BI, yes) as a source of truth, git will be a poor choice and you should look for hosting based on Subversion or Mercurial.
I'd like to suggest that you and your team consider using GitHub Enterprise for your source control solution. There are several features on GitHub that you can take advantage of by hosting your code there, such as dependency analysis and version updates, free CICD with GitHub Actions (50,000 free minutes every time with GitHub Enterprise), dependency hosting with GitHub Packages, a cloud IDE with GitHub Codespaces, and a lot more. 70+ million developers use GitHub today, and you would be hosting your code in the same ecosystem as your favorite open source project, reducing friction for collaboration across private and open source repositories for your team. Also, if you are purchasing Visual Studio subscriptions, you can get GitHub Enterprise licenses bundled with those subscriptions https://docs.microsoft.com/en-us/visualstudio/subscriptions/access-github