I stumbled across a case of canned butter (made in france) at an Asian market of all places today. The price was set at $7.99 per 8.8oz can. I had never tried canned butter, but had always wanted to try it, and have some in my stored goods.
When I got to the checkout, the lady said not for sale, expires today.
Knowing that most canned goods are perfectly fine, well past their "best by" date, I asked how much knowing they were expired. After some deliberation, I asked her how much for the entire case, if I were to buy it to make soap out of, and not to eat. She said $2 each. So I came home with 42 cans of butter.

Does anyone have any long term storage experience with this stuff? How long passed expectation is it really good for?

I'm expecting some next month, I'll let you know.  

I'm in for the AAR from the trip to the ER after the OP tries it out


(I have some as well, and wonder the same thing.  I only bought one can though, and haven't worked up the fortitude to open the can and try it out)

Google "bog butter".

If butter can last 2000 years without a can maybe it can last a few years with a can.

I ate raviolis that were expired seven years ago and I was okay

Most expiration dates are for lawyers.

42 CANS of butter

... Butter is serious business... biscuits approved!!!