Normal on Bioshock Infinite is so easy that you will likely never die. Hard is the only way to play it IMHO. You can be challenged and still see the sights, appreciate the story and not be dealing with frustration. Harder difficulties don't automatically mean frustration, that's only in poorly designed games or where the player refuses to change their approach to situations. You can see this a lot in livestreams when the broadcaster is swearing and pounding his desk because he keeps running into a problem and trying to solve it the same way despite earlier failures.
Anyways Bioshock Infinite is not a frustrating experience on Hard and I would recommend anyone with FPS experience play it that way.
Playing: Bloodborne, Pillars of Eternity, DOTA2 Watching: Vikings, Dig, The Jinx