As an enlightened individual as I'm sure you are, we strive to remove personal bias when possible. This includes measuring statistics. Which can take the form of synthetic benchmarks, but also real life tests, like page load times of notoriously bad news sites, or heavy cpu bound tasks like image resizing in the browser.

If you're not measuring it then it's pretty much subjective, no? You can't quantify what you don't measure.

I don't know how you use Firefox and Chrome (I use both in work) but they behave pretty much identically as far as I can tell, once ads and other crap have been blocked.

The only difference is Chrome is snappier on Google sites and seems to use double the memory to open the same tabs.