Well, I've just completed a 2 month trial run living almost entirely on my surplus of supplies. We did go to the grocer for milk, butter and cheese but all other food was from the pantry. Heated with wood (and a bit of propane), kept the electric on and the internet. Found a few weak spots in my preps, bread uses flour faster than I thought, juice for the kids was thinned with water to last longer and need a bigger supply. In a real SHTF scenario I can see a definite need for a couple of milking goats and some laying hens w/rooster. More detailed report to follow, but overall a complete success with enough of most supplies to last at least another 6-8 months the way we are and due to the fact that weak spots were found and are being dealt with. Another thing to be considered is the strain it put on my relationship w/wife probably due to being up each others backside 24/7. That's a BIG consideration that no one ever seems to address, but I am now!
ETA: Running short on beer but plenty of the hard stuff to last a year or more
What, you don't have canned butter and cheese?
Emergency Food Kits | Survival Food Supply | MRE Food Kits
Uh oh...can't find the butter there or at MREDepot any more...
Might try these folks:
Red Feather Canned Butter from New Zealand