I carry the Hornady Critical Defense in my XD9, but with 17 rounds in the gun alone, I can shoot from sunup until sundown. If the first 5 don't get through the vest, it's head-shots, throat-shots, junk-shots, ankle-shots... and then I pull another 16 out of my pocket.
With the .380 I have to figure on hitting bone, and if that happens a slow-moving hollow-point isn't going to do as much damage as it could otherwise, or as much as an FMJ would. And I just have 6 shots to get the job done.
In close, my aimpoint is the chin, as my target is the medulla oblongata, but that's during no-pressure practice. If I'm trying to shoot while crawling under my truck with two holes in my gut, I want something that has the best chance of making it to the spine and not splattering on a button or a zipper.
I'm not well-versed in ballistic data, but from what I've read, ball ammo in the .380 caliber stands the best chance of getting through the average body based on ballistic gel tests.
I guess what I'm trying to say is that the main shortcoming of the .380 is penetration capability, so I'm willing to trade a larger, shallow crater for one which stands a better chance of hitting the central nervous system.
Just my opinion, and if I'm wrong I hope you'll let me know.
"Guns don't kill people. Male Kennedy's kill people."