I'm not a lawyer, but as I understand contract law, delivering something "close enough" is all that's required to satisfy a contract. Let's pretend everything's perfect except for one brown M&M. I'm sure a lawyer can explain it better, but if everything else is in order, I think Van Halen would have to perform their end of the deal.
You really, really, really missed the point of the M & M's thing.
Before I took a business law class, I figured everything in the contract had to be satisfied exactly. But that's not always how the law works.
I'm talking about U.S. contracts. How would the brown M&M play out in Japan?