The Faculty Data Science & Engineering Fellowship Reviews

There is no doubt that if you get the opportunity to do this, then you should do it. The big benefits are:
Get experience working on a real-world data science project. Build practical skills and build your CV.
Join network of data scientists who are helpful and supportive, even after the fellowship has ended.
Get intense presentation training, culminating in 5 minute presentation during Demo Day.
Get crash course in data science, which provides strong sense of what is useful to know.

Main con is that the short duration of project means you do not have time to best practice in software engineering. You should supplement this course with other ways to learn this skillset (I recommend contributing to open source packages!)