Can we please stop repeating the misleading statement that Firefox is fast enough, because of benchmarks?

When people talk about Firefox being slow, they're not talking about page rendering speeds or JavaScript execution times. They're talking about the longer delays in switching between tabs, in closing tabs, opening a bunch of tabs at once and still having the interface be responsive, and so on. User interface stuff.

Unfortunately, I don't know of any user-interface-responsiveness-speed benchmarks, so it's basically impossible to "prove". But that doesn't mean that people who complain about Firefox being slow are imagining it. The only reason I use Chrome instead of FF on my machine is precisely because the UI is an order of magnitude faster in mundane things -- instantaneous rather than pausing a bit on every little thing.