Not enough reason to buy one, but in the shops I have been in lately, 10mm is probably the most common caliber consistently available versus others on the shelf like .38 S&W, 7.65 Para, .32 Long, and .44 S&W.
In 2009 I was in the Sportsmans Warehouse in Lexington, KY which had 2 boxes of 10mm Auto on the pistol shelf and nothing else.
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