i think for a superb horror shooter.. the ego view is better. less visible area. More "self-" Feeling

But for a Shooter like any other ( see postal 3 ), the 3rd Person view is good ( always make an option for changing to Ego-mode )..

But there are also Games like "Dead Space"... After a while, i never thought that it´s 3rd person.. but the feeling was the same as Ego.. horror pure..

I thinks it´s related to the game.. and your personal feeling about that.