Storage of Large Quantities of Flour

Since you folks helped me out in my quest to find good Bread books.  I figured I might as well ask for your help again.  I have quite a large quantity of flour's, and have been storing them inside of their fifty pound bags, in plastic storage totes.  Now after reading some of my newly purchased books, I find that they suggest storing them in a freezer so they dont go rancid. 

I dont know if it matters, but I have 3 main tyes of flour,

1) Knoxbridge Mills- Premium Spring Wheat Flour, For Artisan Bakers,  Unbleached, Unbromated.

2)General Mills- Gold Medal, All Trumps, Bakers, High Gluton, Enriched Bromated Flour, Bleached.

3)Progressive Baker- Fancy First Clear Flour, Spring Clear Flour

Now I just finished putting 150 pounds of flour into 1 gallon freezer bags, and then insde a large tote in my chest freezer. But before I cut open any more fifty pound bags I was wondering how you folks store your flour?  And what kind of shelf life do you get out of them?

Thanks,

TattooedTonka