I have not yet started casting for 9mm. I have a lot plated bullets that I came into in a trade, and I do not shoot a lot of 9mm. A couple of mags a week with my CC guns. I push the Berry's the same as I do jacketed. So for no problems with them at all.
I will concur with go over sized. Poor fit leads to barrel leading more than anything else. Many people will blame soft alloy, then try harder alloy only to have the same problem.
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.