I am not a Kimber basher and I carry a 3" Ultra CDP that has been a flawless performer. The Solo works well with factory recommended ammo. As a RSO I see a lot of Solo's with feed problems which I attribute to incorrect ammo or operator error.
Many of the other smaller 380's will be far less ammo fussy. The Glock 42 is not a small gun, so if you want a gun that you will be practicing with a variety of ammo, or handloads, and them plan to drop in your pocket and have it disappear, neither of these two may fit what you are actually looking for.
As the owner of one of the ultra finicky ammo guns, a Seecamp .32, I buy factory ammo that will work every time in that firearm and actually shoot it very little.
My 2¢