10mm Auto for sure...I lust after 10mm carbines.
Unlike a lot of pistol calibers, 10mm can really pick up a lot out of longer barrel.
9mm gets practically no boost from the extra burn time...same with .45
.40 S&W...I have no idea what it does, I have never seen the point in it. But I would guess the smallish case cap means you wouldn't make much extra punch with it.
But 10mm...ah 10mm...ever look at 10mm out of a 12" barrel, say? Or a 16? You can load it SMOKING hot and have a serious rifle round on your hands, similar to what a long barrel does to .357.
Frankly I don't see the point in pistol caliber carbines other than 10mm, or one of the rimmed and therefore pretty well lever-only revolver rounds.