I don't get preorders. There are very, VERY few games that I buy immediately on release date because I know that I can't live without them and that I know are going to be extremely awesome. Hell, I'm one of the biggest Halo fanboys I know, and I never bothered to get the Legendary editions for 2, 3, or Reach, because I'm not a bloody idiot and I don't think that the content, kinda cool as some of it is, is really worth the extra asking price when I can be buying something else, like a Fallout game or something.
Call me crazy, but I don't think I need the Valkyrie Assault Rifle to kill the Reapers, or need the special Arctic Camouflage suit to prevent myself from being assassinated from a rank 130 Spartan-IV. To date, developers haven't made it so that preorders break the game.
... To date.
... Now because I said this, game balance is gonna be thrown right the fuck out the window.