Be more productive
In most frameworks, unit tests are a mix of framework code and the code being tested. Lens simplifies things by eliminating the framework code. Lens eliminates over 50% of the work of writing unit tests.
Lens tests are easy to read and quick to write. See for yourself! Take a look at some of the unit tests to see how simple Lens really is.
Catch more issues
Assertion-based frameworks can only catch the very specific issues that you explicitly check. Lens checks all of the side effects from running your source code. As a result, Lens catches everything—fatal errors, exceptions, changes to global variables, surprise echo statements—literally everything that can go wrong. Lens catches everything, always and automatically.