Some is good, more is better, too much is just enough.

Shootin' Buddy's theory on redundancy for your carry gun was that you should "find a gun you like, and buy five copies." That way you'd have:

"One on your hip, one in the safe, one at the local gunsmith, one at the manufacturer being overhauled, and one stored off-site at a trusted, safe location."

Commander Zero seems to have a similar eye toward redundancy, and explains it here. Go read.
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