Having worked with and around firearms for a few decades, I have not seen any significant proof that MIM is any more likely to fail than bar stock. The hyper concern has been a great point of debate, but that seems to be about the worth of it.
I have a Kimber Custom II that has a few thousand rounds through it. I stripped it down completely at 500 rounds. Nothing out of the ordinary, all parts MIM or otherwise working and worn just fine. Again, stripped a few months ago and still nothing to report out of the ordinary. The only part I have HAD to change in the recoil spring and that was at the recommendation of Kimber, not because of a problem.
The range I worked at was a Kimber master dealer and we had a number of models for rent. I would say about 20 Kimber's of different specs available. We had a couple of issues that were related to the small pin for releasing the firing pin block. The "Death Grip" was required to make them actually fire. Our armorer fixed one (we wanted to see if he could do it), the other was covered by Kimber.
Show me some real data that shows the constant failure of MIM parts in Kimber, Colt or Springfield pistols compared to bar stock parts please.
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