I found Firefox + uBlock almost unusable on my Pixel 2XL and use Brave. But I'm glad the options exist at all... I just wish more hardware was more open at Manufacturer End of Live (when they stop updating). So that third parties could continue support better. There's definitely a need for right to repair laws at this point.
Was probably close to launch, almost 2 years ago now... I've been pretty happy with Brave overall, and also found Firefox UI a little frustrating by comparison so didn't worry too much to retry since.
Could very well be better now... I've tended to try FF on most platforms about once a year as my main browser. I do tend to test in it for dev though. My current app doesn't really have a mobile target (mainly deals with scanned images, so desktop is primary).
FWIW, coming from Chrome, the Firefox mobile UI was very frustrating to me also for about two weeks 'til I got used to it. Now it feels familiar and seamless.