I'm speechless, it's almost as if you've both been getting hijacked downloads due to a compromised system or something.

It's been the opposite experience for me, I used to hate Firefox years ago and avoided it for feeling a bit sluggish.  That was years ago though, the Firefox I have now is smooth as silk, hasn't crashed once, doesn't enable things it shouldn't by default, and certainly doesn't install anything other than Firefox without asking.  I even watch YouTube without Flash installed.

So no, it's not nonsense, but providing you're both being genuine, I honestly have no idea what's going on there with your installations, because believe me, if I'd experienced even one of those things, it would not be on my system, either.  Unauthorised installation of drivers, constant crashing, nags for updates and slow performance sounds like your systems have been compromised in some way.

Firefox is just not like that from my experience and I've been using it happily for a fair few years now.  Then again, when I visit mozilla.org, I know I'm truly getting mozilla.org and not some cloned diversion due to a compromised system.  For peace of mind, I always download my Windows version of Firefox using my Debian installation then transfer it via a USB stick, I never use Windows for downloading something as vital as a web browser.  But yup, I'm getting what I should and it's every bit as good as they say it is, I honestly have no problems with it.

Hmmm ... weird.