I have SP101 3", w/ a grip that has a place for pinky finger, but not some extra large grip. If I lay it on top of a glock 34 so the muzzles are the same and the bores parallel, the butt of the SP101 and the base plate of the glock line up near perfectly. I also note that the bore axis is the same on both guns fwiw.
However, I carry the SP101 in warmer weather b/c its easier to conceal than a glock 19 even b/c the area behind the barrel to the rear sights in the auto is bulky and sticks out above the belt line and peeks out past my hip bone, where as the frame of the revolvers missing that big corner does not. This may matter less for like AIBW carry or something, but the extra bulk of an auto in the rear sight area makes a big difference for carrying under a shirt behind the hip.
So, for refernce a 2.5" SP101 w/ like the shorter factory grip will be about the same foot print in terms of the muzzle and the butt as a glock 17. A 3 in or more will be larger in these respects but still easier to conceal behind the hip. A 4" revolver for me would be a bit much for good concealability IWB at leaset while seated as when I sit the gun would be pushed up from the muzzle unless it was about an inch higher from the belt line that it shoudl be for max conceal-ability.
Anway, the SP101 is just for reference. It fails in that it has no rear sight, and 5 shots. You could get the 6 shot 327 fed mag w/ adjustabel rear sight, though I heard someone say the SP101 adj sights are not good, I dunno. But the chambering is good, great energy/recoil ratio w/ good reliable expansion & penetration due to its lighter weight faster and smaller diameter projo. the 85 grain Hydrashok load is pretty light recoil w/ good terminal performance and energy levels. SP101 3" is 28 oz FYI.
Of what you listed, the King Cobra and the Kimber is the best. The 3" king cobra is nice, but no rear sight. It is 30 oz IIRC. The King Cobra 4" target looks really nice, but it is 36 oz empty the barrel may be a bit long, but it comes w/ adjustable sights. The Cobra has small cylinder for 6 shot like old detectives or the Kimbers, but the frame is pretty beefy and in bulk around the cylinder it is similar to the K frame despite the Cobra's smaller cylinder relitve to the K. I really want that 4" target, thou it is a bit too big and heavy to carry for me to be honest. but man it looks nice and is a great execution of a smallish frame revolver. all the king cobras use the oly style detective grip size/shape, that is short for two fingers, so you have options to have a stubby grip, or one w/ more rake etc than you do w/ a K/L frame.
The Kimbers all come w/ really nice sights. Similar cylinder size to the old and new cobras and king cobras, but the frame is smaller thna the king cobra to where the gun is barely bigger than a J frame, really. The 3" w/ its nice factory novak or whatever sights looks really nice. Weight is 25 oz. Seems like the ideal carry gun, either the 3 or 4" for the belt depending on your body and if IWB or OWB, and the 2" models for pocket carry. It is full tange style, but the tang is narrower than J frame so there is a bit more room for grip angle options, but basicually same length as J frame grip frame.
K frames are noticably bigger than these or J frame or SP101 in terms of Cylinder diameter, frame height, grip frame length. L frames are even more diameter and frame height. N frames even more, I mean people might be asking you if you have a colostomy bag.
I would also note that the moon clips for auto chamberings are thicker and stiffer than many 357 moon clips, fwiw. To me, a kimber in 9mm made to take moon clips would be ideal for all season carry, the only draw back that this is not IDPA legal.
@OSU_Buckeyes