From my understanding, and even back in Andrews first book, the "truest" Datil is the second pic from the OP, that pointy one. Now, like all of us, I don't know for sure. I grew some in 2014 and they looked like the dimple bottoms. Even the image in Chasing Chiles (great book about tracking down heirlooms) is that smooth pod. If I had to be subjective I'd say that the pointy c. Chinense is what I would prefer to grow.
Now that I read this before I post it I am no help whatsoever.
Now that I read this before I post it I am no help whatsoever.