He wants a gun he can stick in the glove box and forget about. Changing loads for each person ain't an option, if I understand him right.
Meh. All things being equal, I'd say go with the .357. You can practice with .38 and store it with .357. The first shot will go in the same place irregardless (although you might be a bit startled for the follow-up shots).
I wear a 1.5 " Wilderness Instructor's belt, and it carries my 1911 very comfortably. I've never carried for 12 hours straight, but it's comfortable enough so that I sometimes forget I'm packing. In fact, my 1911 is considerably more comfortable and concealable than my smaller SIG P229. It just seems to conform to my body, and distribute it's weight better for some reason.
Well maybe she needs to sign up for a local NRA course to demistify firearms for her. I know that I enjoy going to the range with my wife and knowing that she can shoot, and shoot well.