I play in 3rd person 99% of the time. When I've spent literally hours creating the look and feel of my character, why would I not want to see the fruit of my labours. if I was to play in 1st person all the time then why even bother making a cool character I'll never see? I do use 1st person for looting though, it's easier to grab the right items for obvious reasons.
First person. I honestly cannot fathom why anybody would disagree (although obviously some people will. People do like to be difficult).
How is it difficult? When i weigh immersion against character design, immersion loses. I put too much effort and work into making my character look just right to spend all my time not seeing him/her. I don't need a 1st person point of view to be immersed in the game, if the writing, acting and gameplay is solid then I am just as involved in 3rd person.
I'm roleplaying a character, not myself, I don't need to see the world through my own eyes to do that.