Reading between the lines I see... Nicely done, but it is only an observation. I know from experience that I need all of those browsers on OS X. Not every site works in Safari, or Chrome nor Fireferet on OS X, we especially like the sites that say please use Internet Destroyer... Then Safari's delevop menu is great for impersonating IE as other browsers. It doesn't always work, but always worth a try.
Disclaimer: On this often shared home computer, I use Chrome, only installed extensions are adblock and two googly docs for work. The missus uses Safari. No issues here so far.