I've read that mushrooms should be stored in a brown paper bag and refrigerated to help them last longer. I only buy whole fresh mushrooms and I think the precut ones would have a shorter shelf life. Around here, I use them so often that they usually don't last especially long anyhow. I don't think canned mushrooms really have any flavor and are basically worthless. One fast food chain has a hamburger with bacon and mushrooms, but when I tried one, the mushrooms were just the tasteless canned ones. Don't plan to order that again.