At first I never used it, always thought typing with two fingers was the fastest (and actually got me the result I wanted).
Nowadays I swipe 99% of the time on my Android phone and it is a lot faster. Especially when your phone learns the words you like to use. It’s not perfect of course and you will have to correct some words down the line (it still sometimes refuses to swipe “Fuck”), but overall I’m faster with it.
Also super comfy for long and complex words when you just roughly swipe it and get the full word written there without errors.
Overall though I prefer to touch type on a proper keyboard on the PC, that’s still the fastest :)
What is actually your problem with Android FF? I use it every day on my phone.
Yes, it’s not as snappy as Chrome, but besides that everything works perfectly. In addition to that: Fully fledged ad-blocker like on desktop, one big reason why I no longer use Chrome on my phone.