I dunno. I installed it on a brand new Win7 laptop two months ago. Since then it's been buggy as hell. Random connection errors many times per day - even when working on websites locally! Then there's the random act of changing my keyboard input so the characters are all out of whack (commas become slashes, colons become dollar signs, etc.) And lately I find it's getting sluggish.
None of these issues have ever happened to me in ANY browser, including IE which I abandoned years ago. And since going back to FF, those issues haven't come up again.
Chrome < Firefox