Saw on reddit
(03-24-2013, 11:22 PM)
It's unlimited in that it means any number of people can use it. Usually when they tweet them out, they'll mention if a code has a certain amount of times it can be redeemed. In this case, there are none. Still only one per account though.
Registered it on PC.
It said that I had 3 new keys, not unlimited.
Havent checked in-game though.
Waiting to use on that new level cap :)
Total truth here. Just use them to pad the piss-poor drop rate of purple guns/shields/mods while you level up, especially in the 35-49 level range. Using them at 50 is kind of a waste.
Do not save the keys until max level, it's not worth it and are best used as you progress.