That´s a great way to check the properties of your brushes, while doing these simple exercises.

Choose 5-7 round brushes which you are usually use for painting. Here is my brush selection:

First test on water absorption:

Testing my brushes for watercolor washes and brush marks:

Brush Elasticity test:

Brush marks with movement:

Finally, let´s see the brushes in practice by painting these two loose floral compositions.

 

Looking forward to seeing your brush explorations and discoveries!