I have always believed that having caliber conversion capability is a good thing, even though you may never use it. In addition to my 4-caliber 1911, I also have the large frame EAA Witness set up to use .45 Auto, 9x19, and .38 Super/9x23 Win. Most of the time it shoots 9x19. If I had a pistol chambered for .40 S&W (I don't), I would still want to get a .357 Sig barrel for it, even though I care nothing about the .357 Sig.