"old thread"
Like other new techniques, MIM technology in guns took a while to mature, and some early MIM parts were made by companies specializing in MIM, not in guns. The results were mistakes in the methodology and the material leading to problems. And since nothing ever dies on the internet, some folks keep posting old pictures to promote some agenda of their own.
But the gun makers have gotten their acts together on MIM and today, IMHO, it is a perfectly good way to make complex parts with (usually) no subsequent machining required.
Saying that MIM allows the parts to be made cheaper, not better, implies that MIM parts are somehow worse than parts made by casting, forging or stamping. That is simply not true. Any engineer will select the method of production for what he wants a part to do. No one would suggest a polymer sear, or a plastic hammer. But no one would want to carry a rifle with a solid machined steel stock very far, no matter how strong it might be.
And if MIM parts are cheaper, so what? I wonder if the folks who cling to the idea of forged parts, hand filed to fit, would like to pay for that kind of production, or see guns restricted by price to only the very wealthiest. Unlike those folks, I am not a millionaire, "dot com" or any other kind, and I appreciate being able to buy guns at some reasonable price.
I have a Model 1899 S&W M&P, the first M&P model. If that gun were still being made today, like it was made 112 years ago, it would cost at least $2500, maybe $4000. Some folks who could afford it might like that since they would be among the wealthy elite who could own a gun. I am glad good quality guns are "cheap" enough to be affordable for the peasants, like me.
Jim