Kentucky - follow your instincts!
Here is the 1911 in my stable that "lights my fire":
The 3" Ultra CDP differs from the 3" Ultra Carry only in the extras that are included. By extras we are talking about night sights, frame finishing, frame checkering,
heavy carry melt, rosewood grips, different trigger, etc. Kimber is the only manufacturer to offer a 3" 1911, I think that says something about their engineering.
Mine is accurate and reliable. It did have a tendancy to lock the slide back before the mag was emptied; while I could have contacted Kimber about it I instead did some reading & found that condition is not uncommon in a short barreled 1911. Seems the increased recoil allows the cartridges to jump forward a little in the mag, and the nose of the bullet will nudge the tab on the slide stop, move it up & activate the lock. This only happened to me when shooting 230g hardball - any defensive HP in any weight functioned fine - but I shortened the tab a little & now it functions just fine. Had that not have worked, I would have contacted Kimber.
I liked my Ultra CDP so much, I bought a 5" Classic Stainless as a stable mate. This is the bone stock full sized SS 1911. This gun is every bit as reliable as my CDP - and maybe a little more accurate, probably due to the added 2" of barrel. I'm close to sending this one off to a pistolsmith for some work. Not that it needs any, but it will be interesting to compare an aftermarket custom to a factory custom.
I wouldn't be concerned with the critics of MIM technology. It is here & it is here to stay. Ruger is using it for parts in their semi-auto rifles. I know, because the company I work for owns a company that manufactures tungsten alloy and also machines it into parts. They lost the Ruger account to competition from a MIM house. In fact, Ruger has so much success with it that they wouldn't consider allowing my firm to bid on the work using similar technology. I'm not sure how many parts Colt or SA uses that are MIM, but I would bet there are a few & if not now, they will be.
Plastic MSH? Yes, Kimber uses it & I would prefer steel in my 5" gun. I'm going to swap it out on my Classic Stainless, but I'll leave it on the CDP as it is lighter in weight. But that is simple my own preference, the factory unit works fine. If I'm not mistaken, Colt also uses plastic. Not sure about SA.
Kimber, Colt, & SA all make nice guns. I would suggest Kimber, you won't regret it!