Many people are sceptical about testing through the user interface of an application. They prefer subcutaneous tests.

Typically, the arguments against testing through the UI are:

• The tests run much slower than well-isolated unit tests
• The tests are brittle, because the UI is one of the fastest changing parts of the application

In general, I fully agree with these arguments.
But today, I want to kick-off a different kind of discussion:
What positive experiences did you have with testing through the UI?