Pros
The biggest benefit of working for Thoughtworks is the culture. In all levels, people have a very strong habit of communicating clearly, and feedback is shared without barriers, this creates a great environment to grow and improve. This open culture allows for very interesting conversations across all levels, and makes the company feel very flat. It also allows for folks to support each other in their growth journeys. For those more aligned with social causes, Thoughtworks offers a lot of space to explore how to contribute to these causes without risking their employment. Normally, the client rotation schemes also allow you to explore a great breadth of technologies, and even "switch" roles if you so desire.
Cons
Not all clients are the same, and if you are staffed in a difficult client, your experience will be lessened. This can also affect the previously mentioned client rotation cadence. A lot of the processes rely on finding the correct person to talk to, which can be difficult as the company scales.