I've tried them on backpacking trips and while their light weight is a plus, I didn't really enjoy them and wouldn't want to rely on them for more than 2 or 3 days at the most. I found I felt fed up (in every sense of the term) long before I was finished the serving and ended up being hungry way too soon after. And, as a practitioner of the 'leave no trace' ethic, I had to carry a bag o' sludge with me until I could next dispose of it, which kind of negated the light weight of the uncooked meal.
Try a couple at home and see what you think.