Congrats!!! I love my PM40.
When selecting ammo bare in mind that for the most part .45acp ammunition is designed to be fired from a 5" barrel, and as a result loses a lot of potential velocity when it's limited to a 3" barrel. The temptation is therefore to go with a lighter weight bullet to improve expansion at reduced velocities. But I don't think that this is the answer. For one thing the designers are pretty bright and engineer lighter bullets so that they will not over-expand and fragment at the expected higher (5" barrel) velocities. This often entails using a harder alloy and puts the same expansion constraints on lighter/faster that you see with a 230gr projectile.
I did a lot of research when I was shopping a load for my 3" Kimber. I narrowed my selection to (no order) the Speer 230gr Gold Dot for Short Barrels which is optimized for 4" barrels; the 'LE only' Federal 230gr Tactical Bonded; and the 'LE only' Winchester 230gr Ranger-T. I eventually settled on the Federals based on both price/performance from 3" pistols and ready availability from Internet retailers.