I found it to be fast and easy to set up. I reviewed a number of testing frameworks for vanilla JS projects, and it came up on top, even though I hoped it wouldn't (I try to avoid all Facebook products).

I can't remember the specifics, but I think it was a mix of having nice reporting built in, easy to spy on or mock our ESModules, and there are a lot of other developers using it, so it was easy to find solutions.

It mostly "just worked" and didn't require adding other libraries to handle mocks and spies.