Brass?
IMHO it depends on what you are doing. If you are a "benchrester" where success or failure is measured by +/- .002" then brass brand probably makes a difference. I have a rifle that shoots minute-of-prairie dog out past 400yds consistantly and have a few kills out close to 600yds all with Remington brass. Am I saying Remington brass is the"best"? NO! I'm saying for what I do Remington brass meets my needs.
GOOD LUCK and GOOD SHOOTING!!!