Good question. I have previously used Firefox, Chrome and Chromium. I make heavy use of multiple profiles in the browser. Firefox has never been very good at managing and profiles in the browser. With all the Chrom{e|ium} based browsers, it's a click away.

Firefox also doesn't do webapps (at all?). I like to have a bunch of web "Apps" which I put on my launcher for easy access. I like being able to alt-tab between websites, rather than switch to a browser than have to switch tabs.

I've had multiple occasions where Chrome and Chromium have completely eaten my profile losing all pinned tabs, cookies, extensions and any session information.

With Firefox it's broken in weird ways for me. Most recently it would just load white blank pages for every tab I had open.

I've also had poor performance from Firefox and Chrome, in terms of eating RAM and CPU inexplicably, constantly.

Having tried Firefox and Chrome extensively, and had bad experiences, I thought I'd give Edge a try.

Edge has the same easy profile management of Chrome. It has never died and eaten the session, nor decided to render all my tabs in white.

Edge also has vertical tabs built in, which I use. It also has an effective tab sleep tool which means idle tabs aren't eating resources.