A quick performance benchmark test on Unity, comparing async usage with Unity Coroutines.
Open the project on the Unity Editor, and select Window>General>Test Runner. On the Test Runner Window, select Play Mode and then Run All. This will run all tests in a runtime simulation.
The tests produce a json output on the Output folder. On this same folder there is an Office Excel file which displays the data in a comparison chart, that you can easily update to match your tests.
You can change test parameters, such as simulation count and initial threshold, on the BenchmarkSettings asset under Assets/Resources.
Feel free to contribute to these tests if you wish. My only purpose with this repository is to answer questions with solid testing data. If you think the tests can be improved or are generating unreliable data, please add your own contribuition as this will help the entire community.