I will sum it up. FF is the best for options ie spell checking, IE is the best for uh not sure, Chrome is the best for speed.
I alternate between chrome ff and opera, i have chrome and opera because they take less time to start up usually.
i use opera in the mornings, and safari/ie/firefox/chrome/and-this-random-korean-browser-my-dad-gave-me in the afternoon and at night.