TexasCHLforum.com

>Why do manufacturers insist on using them when people detest them, and change them out quickly?

cause they're cheap (?).
If Bob's 1911 Factory is turning a profit, he may not care that the first thing his customers do is gut the product and replace all the internals. That's been common practice in the 1911 world for some time, partly because it used to be that not all 1911's were really reliable out of the box. (plus some people just like to customize). I think that changed in a big way when Kimber started selling 1911's with custom features right from the factory.

> I have never had a MIM part break, but others have.

I have: ParaOrdnance Series 80 plunger lever. Replaced all 5 parts with Cylinder & slide TiN coated parts.