I notice certain UI elements run better in Firefox. Let's take tabs, for example. I've sometimes ran into a bug where Safari will hang when opening Private Tabs for the first time. I'm big on buying gifts, obviously, so I don't like lag in that scenario. I have more times of Safari reloading the page when going back than Firefox, from what I've noticed. Then we have scrolling being smoother on Firefox for whatever reason.
It also seems to go faster, but I can't prove that. Weirdly enough, Firefox has a slightly smaller Jetstream score. I ran Firefox first, if that matters.
