Everyone is different, and its better to shoot the way that makes you comfortable.
Me - I cant shoot unless I have a kisser button. I have gotten so used to it. I can out it on my lip to where it feels the same exact way every pull. If something is off key, I'm leaning, or twistin my arms in any way.....I can tell through the kisser button. It's all about what your comfortable with. That will, in the end, give you confidence.