[Ken]

And is there any difference in their reliability (and the reliability of other 1911-based .38 supers) as compared to the same model in .45 acp?

[Longbow]

I think Kimber offers it in the full size version only. The reliability is probably good, since the O.A.L. of the two cartridges are close to one another (min. of 1.215?)

[David Roberson]

Kimber offers a full-size and a Commander-size gun in .38 Super, or at least they claim to do so. I've never seen one of the Commander-size ones except in pictures. I got one of the full-size stainless versions last year and it's a great gun -- certainly the equal of its stainless .45 brother which I got about four years earlier.