I'm not just looking for an advantage (and not talking about competitive games, importantly. I know how important FOV equality is at that level), I'm just looking for immersion. Skyrim with an ultra-wide FOV let's me see approaching enemies a little sooner, but it looks absolutely atrocious. Beyond that, human vision can cover a 270-degree field if you allow eye movement (but not head movement). That's 90 more degrees than any shooter will give you.