You won't get the special armor from the pre order, but you if you don't feel like buying the DLC, you can add the following lines to the end of your XComGame.ini in C:\Users\<username>\My Documents\My Games\.
[XComStrategyGame.XGCustomizeUI] bArmorDecoAvailable=true bArmorTintAvailable=true
This will allow you to get the color customizations without the extra armor.