How Long Freeze-dried Foods Can Be Kept

I use the Mountain House Freeze Dried foods for camping as well as, backpacking trips.
However, having these food packs in your home for emergency foods in case of a local disaster is a great idea as well.
You boil water on your camp stove or grill, or backyard fire and you have a good meal. It is important however, to rotate them out and use the oldest packs first. I was looking over my supplies and found a pack from 2009. They say that each pack should be stored for 3 years. Last year I had lived in a third floor apartment that got very humid as the window placement did not give good ventilation. I was worried about losing my small food supply to hot weather.
However, tonight I had the 2009 food pack for supper and it was very tasty. It was creamed potatoes and a vegetable. The sauce was still good and I rest assured that the rest of the meals are still in perfect condition.
They say 3 years, but the colder your store-age area, the longer these food packs can be kept. I am not crazy for MRE's, do to the high salt content. I have never been disappointed with a Mountain House meal.
What is your opinion on freeze-dried foods? Any brand that you prefer? Have you ever had any go bad or lose flavor from storeage? Which brand do you carry on backpacking or camping trips? Or do you dry your own meals? Please share your thoughts on this topic.