I tune all my monitors to run darker, it might not look as pretty in most instances, but all my collection is operated commercially and I try to do this to curb burn-in.
for what it's worth, back before I understood the concept of brightness and contrast, I used to run them high on an Extreme Hunting and the credit screen did burn in, and the same thing happened on Street Fighter Alpha 2.. which is now 3, but you can see the SFA2 credit screen burned in now too. lol
the easiest way to do it is to find something of a happy medium between the Screen/G2 and Brightness adjustments to where black backgrounds are not visible, you don't want black to look like a brown, for instance, you don't want to see it at all... that's what your Brightness should be set at. Contrast I was told you run as high as to where bleeding of text (usually you'll see green streaks) is gone.
once you do those, now set them both a little bit lower to your liking. it cuts down the possibilities for burning in then, cause above-mentioned phosphors won't be running as.... hot?
yeah.