Hitboxes

As the title says. Hitboxes. A headshot, a body shot, etc. Does every player character have the same sized hitbox? The Irathient character I had seemed larger than a human I made, but how does this affect hitbox size? Is it possible to shoot at a character but miss because the hitbox was smaller than the polygonal model?

How does costume change hitboxes? I wore some heavy armoured suits as costumes that increased my head size and body size. Would shots pass through phantom edges, or is the hitbox expanded to match costume. I also had the stalker costume, which people may know was skin tight and didn't increase my character model's profile.

In pvp you're given a specific costume, and you can only change the head (as of the beta) is this to avoid hitbox adjustment?

Wish I'd had this thought while the beta was still active so I could've tested it.