I am a lefty shooter, and have only ever fired a righty AR. Its what I know. The only mod I am doing is an ambi safetyplike what others have done. The brass never bothered me-but, then again, I never knew anything else.
When I first went into the Army, we had old post Viet-Nam M16's-they didnt have brass deflectors. Without one, shooting sucked. When I used one, shooting sucked-the huge piece of plastic in fron of my face was a distraction. When we finally upgraded to the A2-that little piece of metal sticking out was the greatest thing I ever saw! Too bad it took them that long to figure it out...