I am primarily a back-end/services/middleware dev and don't do much front-end stuff these days.
When I do though, I use Firefox's dev tools and I don't know...I'm not sure what I'm missing?
I have Chrome on this machine too and have tried the dev tools there but I beyond layout I don't know what the differences are or what Firefox's dev tools are lacking.
Every release they publish a blog post with new DevTools features, here's the latest one from January 2018 . If you scroll to the bottom it has a section titled "Discover other DevTools features", which provides a long list of features they've been adding over time.
Their console autocomplete is just amazing. If you type `document.querySelectorAll('body')`, it shows you a preview of the result without even having to hit enter. Then if you type a period it shows you that the constructor is a NodeList, as well as its methods. They go over many of these features in their May 2018  blog post. Keyboard navigation has continually been improving as well.
There's no huge killer feature, it's just very solid all-around. Over the years it has remained miles ahead of the competition. With that being said, I still use Firefox as my daily-driver, and I'm perfectly happy with their DevTools for many tasks. And they're actually superior for certain tasks, for example, when working with `display: grid` and `display: flex` . I usually switch over to Chromium while I'm actively developing or debugging something, but I don't think there's any need to limit yourself to just one tool.