Most of the comments here are about using or not using Firefox, depending on it's features as compared to primarily Chrome. However, for me, it is not about being better or having more features at all - it is because I like Firefox and want to support Mozilla and believe that Google should not control the web. It is somewhat similar to the free software vs. open source debate - one should use free software not because it is better, but because it is the right thing to do (I understand that not many people agree with this philosophy, which is fine).
Having said that, all sites which I regularly use work perfectly for me in Firefox with acceptable performance. So I never found a reason to switch at all. Rarely, I come across a website which is "best viewed with Chrome"; my default action is to close that site immediately.
Having said that, all sites which I regularly use work perfectly for me in Firefox with acceptable performance. So I never found a reason to switch at all. Rarely, I come across a website which is "best viewed with Chrome"; my default action is to close that site immediately.