Performance is worse in general. It's something you'll have to try for yourself, but websites generally load worse on Firefox.

Some Google websites will intentionally block you, or serve you older pages if you're on Firefox. Using a plugin to modify your agent string is a work around, but also makes it seem like you're using Chrome within their analytics which isn't a good thing.

Like I said, firefox had a bug where printing shipping labels wasn't working. Took me months of reporting before it was just recently fixed. No one ever acknowledged my issue, and still to this day the bug report was never marked as fixed. I had to run my company from a chromium based browser for months because of it.

The Android app is ass. It's so clunky and runs like crap. At least it has ublock origin, which is nice. Only recently did firefox finally get pull to refresh, and it's a buggy pile of crap lol.

I think it's good to use Firefox. Chromium based future isn't a good thing, and Chrome is evil trying to block ad blocking with manifest v3, and being literally the only Android browser without ad blocking. Even chromium based Edge has ad blocking on Android.

People on Lemmy are hard core enthusiasts at the moment. I think anyone that says anything negative about things enthusiasts are really passionate about, like Firefox, Linux, etc, will be downvoted.

I think it's important to not be a fanboy and to be aware of shortcomings. I'm not against Firefox. It's the only browser I use now, and I highly suggest everyone give it a try, but I'm also not going to pretend it's some amazing experience. It's clunky, but it's run by a good foundation, has some neat features Chrome doesn't, and it's helping prevent an even larger chromium monopoly. Give it a go! Just be aware it's not perfect, and I think you'll be more likely to stick with it long term.