Interesting. I unfortunately can not add it to my account. I receive a message "Try that again - Something happened on our end. Waiting a bit might help."
Will not have a chance to utilize and somehow ended up with two -
Doom 3 Beta codes (note: put them thru a text reverser before redeeming code)
Z3HGY-7DDQR-72VHC-XWXRV-W7RJ4
ZXJJ2-69DJV-WRGG2-WC4C2-H4YDX
Protip Regarding Gears of War 2 - Rent Gears of War Ultimate Edition from your local video game rental location for a night (Family Video for me). Play the game a few hours. Get a code for Gears of War 1, 2, 3, & Judgement in a few weeks.