I learned the hard way many years ago to always taste canned tomatoes (any type) before using them.
Today I was making about a gallon of BBQ sauce (utilizing about $20 worth of bourbon!), when I decided to compare the flavors of Muir Glen vs. Contadina tomato pastes. Yikes, the MG had a horrible tinny taste! (was an older can)
Fortunately, I had yet to mix in the cans of tomato paste, and was able to spoon out the "offending" paste.
P.S. I had a brand new can of Muir Glen tomato paste on hand; it is much better than Contadina.