............and human skin hasn't gotten any thicker in the subsequent 150 years.
Perhaps not, but on average we certainly HAVE gotten fatter.
Sorry I couldn't resist.
Pick which ever one you can shoot the most effectively. 9mm, .40s&w, 45acp....they can all make equally good or poor choices depending on how effectively they are used. I like shooting .40s&w handguns, a lot of people don't; only you can decide what is the best choice for your situation.
---Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.---
---Enlightenment is the ability to take infinite pains---