Thanks for your input guys. I've decided to leave well enough alone.
Here's a few threads I dug up on the Internet.
My take aways:
1) A lot of the comments I read state that MIM parts are just fine.
2) It's about $300 worth of parts.
3) MIM part breakages are rare and typically occur during break in. If they make it through this period, they usually last as long as a tool steel part.
4) Kimber's MIM quality issues were a result of the policies of their CEO, (Cohen) who has moved on to SIG.
MIM parts have decent longevity
Springfield, Colt, and S&W use MIM parts in a number of their 1911s
Wilson Combat uses them in some of the their guns. There is a quote in this thread where a representative states that tool steel parts are overkill.
But, if someone wants to replace the parts, here is a solid sounding recommendation:
Replacing the MIM parts is easy. Buy a "drop in" trigger kit (sear, hammer and disconnector) from Cylinder & Slide (I have two of their Tactical II kits, one on a Springfield another on a Caspian/Colt, both dropped in and yielded a little over 4.5 pound trigger pulls), fit a new thumb safety (I've used Ed Brown parts, which are partially machined investment cast, but my next one will be EGW machined from bar stock), grab a slide stop from EGW, Wilson or Cylinder & Slide (forged or machined from bar stock), a firing pin stop from EGW, a magazine catch/release from EGW and a new ejector.
You probably also want to replace the extractor as well, again, the EGW heavy duty one is really nice (I have one in that Caspian/Colt).
You could do this in stages, but you're looking at $300 in parts, installation would be extra. Most of the parts are going to drop in without modification. The new thumb safety will need to be fitted to the new sear. There are good directions, but it's a critical fit. I messed up two before I got the hang of it.
As for suppliers, be careful, many use MIM. Avoid McCormick, as they are all MIM. EGW is a safe bet, they don't do MIM at all. Some Ed Brown parts are investment cast, though Chuck Rogers swears by them (there is an explanation stickied in the gunsmithing section).
As for me and MIM, well, I am not a fan, but I'm not a eradicate MIM just because it's MIM either. Three out of five of my 1911s have MIM ignition components, and both my SW1911 and Springfield WWII GI have a few thousand rounds through them without incident. The Smith & Wesson even has a nice trigger pull at a hair over five pounds.
Anyway, I handled the gun while I filled out the paperwork to start my 10 day waiting period. It's got a much tighter frame to slide fit than my Springfield and I'm looking forward to firing it.