There is realistic risk, then there is just fear and anal obsession. Significance and meaning gets lost in the debate.
I don't think the MIM parts controversy has proven itself in any clear direction-- thus my conclusion is that because there is no direction, then there is no significance.
Obviously, competitors will try to sell you products and services, preying on this over obsession. Like Lexus, Kimber is very aware of their standings in their market, and very unlikely to risk reputation on a part that will not hold up as intended.