Depends on what you want to test, I guess. If you want to test UI widget behaviour (not just business logic), then jsDom probably isn't the right tool and you

Depends on what you want to test, I guess. If you want to test UI widget behaviour (not just business logic), then jsDom probably isn't the right tool and you need a browser. E.g. if you need CSS measurements or more tricky DOM behaviour. It's not entirely clear to me why you'd want a headless browser though. Once you're already running a browser, you might as well run a full one, and also get the debugging capabilities.