the only advantage to the little plastic and metal semi autos is that they are somewhat easier to find.
the pros and cons of both are increased when size of the actual weapon shrinks. but overall they are still there.
but the thing no one has really touched upon is this, the bullets PROVEN to always expand in the tiny semi autos are the most expensive ones on the market, and are the hardest to find. the older standbys that work fine in a standard barrelled service auto, well become rather insufficient in expansion.
but the idealized loads like a 158 grain lswchp out of your jframe performs almost the same as it does from a 4 inch barrell.