Hey Henry!

Check out this brief article about this topic: https://itnext.io/how-to-use-jest-in-angular-aka-make-unit-testing-great-again-e4be2d2e92d1 (I wrote it).

In short: the testing experience with Jest is much better and more stable than using Jasmine + Karma. You also do not need a browser like Chrome (headless) to run the tests (e.g. on a CI tool like Jenkins).