chrome seems to be the best for me personally.
I use a macbook though so I'm not sure if it's different for other people =/ I know for me, (just one example) if I use firefox, I have to go to cata to refresh where my health bar is (the % full) if I tab out for something it stops the live progression of regening life/mana. In chrome, it doesn't stop when I tab out for some reason
there's a couple little quirks like this that makes chrom > for me