I use Firefox and Chrome. I've never had to switch to Firefox to get a site to work correctly for me, but I have had to switch to Chrome.
If a family member asks me what to use, I would tell them to use Chrome just because it's likely to be a better experience for them.
It’s a known quantity — it’s what I’m currently using, and it works.
Well lets not act like Firefox is not known. Its been pioneering browser for years and it's in no way inferior to chrome. It's also indepedent and you dont have to send all your data to google when you use it.
It is slower than Chrome. That's enough to me not to consider Firefox, given that speed is everything I care about.
I wish people would try current version of Firefox.