Where I work, over the past 2-3 years we've used B+, Pi 2, and Pi 3 (all running Raspbian) for public display screens and browser performance is terrible on all of them. Even the Pi 3 is unable to play YouTube videos without freezing for 10-30 seconds while it buffers and skipping a ton of frames throughout.

If you have video files or use e.g. youtube-dl and then play video back with omxplayer it's nice and smooth (although using the --loop option seems to make the video freeze after several hours/days; memory leak?). Our solution was a 2-line bash script to start a new omxplayer instance when the previous one finishes ad infinitum until you Ctrl+C, and that's run for 7 or 8 months now without a hitch.